Topical formulations for delivery of hedgehog inhibitor compounds and use thereof

ABSTRACT

Compositions for topical administration of a hedgehog inhibitor compound are described. In one embodiment, the hedgehog inhibitor compound is patidegib and the topical composition comprises the compound in a solvent system of a monohydric primary alcohol and a polyol in a w/w ratio of between about 0.9-1.8. In another embodiment, the hedgehog inhibitor is itraconazole and the topical composition comprises the compound in a solvent system comprising a monohydric primary alcohol and an optionally lower alkyl end-capped oligomeric alkylene glycol in a w/w ratio of between about 0.8 and 2.6 and a fused bicyclic ether. Method of using the compositions are also described, where in one embodiment, the compositions are topically applied for treating or preventing basal cell carcinoma.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 62/171,117, filed Jun. 4, 2015, and of U.S. Provisional Application No. 62/275,185, filed Jan. 5, 2016. Both applications are incorporated herein by reference in their entireties.

TECHNICAL FIELD

The subject matter described herein relates to compositions for topical application of a hedgehog inhibitor compound and to topical delivery systems for administration of a hedgehog inhibitor compound.

BACKGROUND

Drug administration by topical skin application of a drug offers distinct advantages over conventional administration methods. For example, some drugs cannot be absorbed in the digestive tract and intravenous and subcutaneous administration by injection is inconvenient and invasive. Oral and intravenous administration for treatment of a localized skin condition is undesirable as the drug is circulated systemically rather than restricted to the localized, diseased area. Yet, due to the protective nature of skin serving its intended function of being resistant to external perturbations, only a limited number of drugs are bioavailable via topical application.

Drug administration via the skin may be transdermal or intradermal (also referred to as local or dermal). Transdermal administration involves transport through the skin such that a therapeutic amount of the drug is achieved in the systemic blood circulation. Intradermal or topical administration of a drug involves entry of the drug across the stratum corneum for a cutaneous or local skin effect; that is the pharmacological effect of the drug is localized to the intracutaneous regions of drug penetration and deposition. Preferably, intradermal absorption occurs with little or no systemic absorption or accumulation. Intradermal absorption of a drug involves partitioning of the drug from the applied vehicle into the stratum corneum; diffusion of the drug through the stratum corneum; and partitioning of the drug from the stratum corneum into the epidermis. In contrast, transdermal absorption further involves diffusion of the drug through the epidermis; and capillary uptake of the drug for circulation in the blood.

Whereas transdermal compositions are intended to deliver drugs for systemic circulation, a different composition would be needed to deliver the same drug intracutaneously. Topical formulations that achieve delivery of a drug across the stratum corneum and retention of the majority of the drug dermally such that it does not enter the blood stream in significant amounts are complicated to design and require innovative approaches. Several factors determine the permeability of the skin or of specific layers, in particular the stratum corneum, of the skin to drug compounds. These factors include the characteristics of the skin, the characteristics of the drug compound (e.g., its size (molecular weight or molecular volume), its lipophilicity/hydrophilicity, its polarity), the dosage of the drug compound applied, interactions between the drug compound and the delivery vehicle, interactions between the drug compound and the skin, and interactions of the drug and the skin in the presence of the ingredients in the delivery vehicle. As a result of the multitude of factors involved in administration of a drug intracutaneously, it is generally accepted that whether intracutaneous delivery of a drug compound can be achieved in an amount sufficient for therapy is uncertain. Penetration enhancers are commonly used in transdermal delivery to achieve penetration of a drug across the stratum corneum typically to provide for systemic delivery of the drug, rather than its retention in the epidermis or dermis. Thus, topical administration, while desired from a patient convenience and drug delivery view, has been largely unsuccessful for many compounds as evidenced by the relatively few drugs approved for topical administration.

A condition that would benefit from a topical formulation that achieves intracutaneous delivery of a drug is basal cell carcinoma (BCC), the most common form of skin cancer in the United States. BCC is observed in the general population typically on sun-exposed areas of the skin, and in subjects with the Basal Cell Nevus Syndrome, also known as Gorlin syndrome, an inherited condition where the skin is prone to developing BCCs. Although BCCs rarely spread (i.e., metastasize) to other parts of the body, they can be destructive and disfiguring. A variety of surgical and non-surgical therapies are available for BCCs. Nonsurgical therapies include radiation therapy, chemotherapy, and immunotherapy. These therapies can be useful for definitive treatment of primary tumors and some recurrent BCC tumors and for relieving symptoms associated with inoperable tumors. However, some of these therapies also can have significant unpleasant side effects. Side effects of radiation therapy and certain chemotherapies are well documented. One form of immunotherapy involves intralesional injections of interferon. While interferon therapy can be effective against BCC, the multiple intralesional injections can require several clinic visits per week for many weeks and are painful. Thus, there remains a need for a non-surgical therapy for BCC that offers better patient convenience.

The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.

BRIEF SUMMARY

The following aspects and embodiments thereof described and illustrated below are meant to be exemplary and illustrative, not limiting in scope.

In one (or a first) aspect, a composition comprising a hedgehog inhibitor compound and a solvent system comprising (i) a monohydric primary alcohol and a polyol in a w/w ratio of between about 0.9-1.8 and (ii) a buffer or a fatty acid comprising between 13-22 carbon atoms, wherein the hedgehog inhibitor compound is present in the solvent system between about 0.1-10 wt % is provided.

In another (or second) aspect, a composition is provided that is comprised of a hedgehog inhibitor compound and a solvent system, the hedgehog inhibitor having a saturation solubility in the solvent system of between about 0.1-10 wt %, preferably between about 2.5-8 wt %, and the solvent system comprising between about 15-60 wt % of a monohydric primary alcohol and between about 10-50 wt % propylene glycol.

In still another (or third) aspect, a composition is provided that is comprised of a hedgehog inhibitor compound and a solvent system comprising (i) a monohydric alcohol comprised of at least one of ethanol and benzyl alcohol and propylene glycol, the monohydric alcohol and propylene glycol in a w/w ratio of between about 0.9-1.8 and (ii) a buffer or a fatty acid comprising between 13-22 carbon atoms, wherein the hedgehog inhibitor compound is present in the solvent system between about 0.1-10 wt %.

In one embodiment, the monohydric alcohol is of the form R—OH, where R is selected from methyl, ethyl, propyl, butyl, and pentyl. In another embodiment, the monohydric alcohol is represented by the structure C_(n)H_(2n)—OH, where n is 1, 2, 3 or 4.

In yet another embodiment, the monohydric alcohol additionally includes benzyl alcohol. In still another embodiment, the monohydric primary alcohol is a combination of ethanol and benzyl alcohol. In another embodiment, the primary monohydric alcohol comprises phenoxyethanol.

In another embodiment, the solvent system further comprises diethylene glycol monoethyl ether.

In another embodiment, the fatty acid is a saturated fatty acid. In one embodiment, the saturated fatty acid is selected from myristic acid (C14), palmitic acid (C16), stearic acid (C18) and arachidic acid (C22). In yet another embodiment, the saturated fatty acid is iso-stearic acid.

In one embodiment, the hedgehog inhibitor compound is present in the solvent system in an amount between about 2-8 wt %.

In one embodiment, the solvent system comprises between about 1-3 wt % benzyl alcohol. In still another embodiment, the solvent system further comprises diethylene glycol monoethyl ether. In yet another embodiment, the solvent system comprises diethylene glycol monoethyl ether and does not comprise benzyl alcohol.

In still another embodiment, the monohydric alcohol is ethanol and the ratio (w/w) of ethanol to diethylene glycol monoethyl ether is within about 10-20% of the ratio (w/w) of ethanol to propylene glycol.

In another embodiment, the monohydric alcohol is ethanol and the ratio (w/w) of ethanol to diethylene glycol monoethyl ether is the same as the ratio (w/w) of ethanol to propylene glycol.

In one embodiment, the solvent system comprises a buffer at pH 7.5.

In yet another embodiment, the composition further comprises a gelling agent. An exemplary gelling agent is, in one embodiment, hydroxypropylcellulose.

In one embodiment, the hedgehog inhibitor is patidegib or is a combination of patidegib and itraconazole. In another embodiment, the hedgehog inhibitor is itraconazole.

In another (or fourth) aspect, a composition is provided that is comprised of patidegib and a solvent system comprising (i) ethanol and propylene glycol in a w/w ratio of between about 0.9-1.8, (ii) diethylene glycol monoethyl ether, and (iii) a buffer, wherein the hedgehog inhibitor compound is present in the solvent system in an amount between about 0.1-10 wt %.

In one embodiment, the ratio (w/w) of ethanol to diethylene glycol monoethyl ether is within about 10-20% of the ratio (w/w) of ethanol to propylene glycol. In another embodiment, the ratio (w/w) of ethanol to diethylene glycol monoethyl ether is the same as the ratio (w/w) of ethanol to propylene glycol.

In another (or fifth) aspect, a composition is provided that is comprised of patidegib and a solvent system comprising (i) ethanol, benzyl alcohol and propylene glycol, the ethanol and benzyl alcohol in a w/w ratio with propylene glycol of between about 0.9-1.8 and (ii) a fatty acid comprising between 13-22 carbon atoms, wherein the hedgehog inhibitor compound is present in the solvent system in an amount between about 0.1-10 wt %.

In one embodiment, the fatty acid is a saturated fatty acid. In another embodiment, the saturated fatty acid is selected from myristic acid (C14), palmitic acid (C16), stearic acid (C18) and arachidic acid (C22). In still another embodiment, the saturated fatty acid is iso-stearic acid.

In one embodiment, the solvent system comprises between about 1-3 wt % benzyl alcohol.

In another (or sixth) aspect, a composition is provided that consists essentially of patidegib and a solvent system comprising ethanol and propylene glycol in a w/w ratio of between about 0.9-1.8, wherein the patidegib has a saturation solubility in the solvent system of between about 2.5-8 wt % and wherein formulation provides an in vitro concentration of patidegib in the dermis of greater than about 250 μM 48 hours after topical application.

In one embodiment, the solvent system further comprises diethylene glycol monoethyl ether and a buffer.

In another embodiment, the solvent system further comprises a fatty acid comprising between 13-22 carbon atoms.

In still another embodiment, the solvent system further comprises benzyl alcohol.

In another (or seventh) aspect, a composition is provided that consists essentially of patidegib and a solvent system consisting of ethanol and propylene glycol in a w/w ratio of between about 0.9-1.8, diethylene glycol monoethyl ether and a buffer.

In still another (or eighth) aspect, a composition is provided that consists essentially of patidegib and a solvent system consisting of ethanol and benzyl alcohol in a w/w ratio with propylene glycol of between about 0.9-1.8 and a saturated fatty acid comprising between 13-22 carbon atoms.

In yet another (or ninth) aspect, provide is a composition comprising a hedgehog inhibitor compound and a solvent system comprising (i) a monohydric primary alcohol and an optionally lower alkyl end-capped oligomeric alkylene glycol in a w/w ratio of between about 0.8 and 2.6 and (ii) a fused bicyclic ether having from 8-14 carbon atoms, wherein the hedgehog inhibitor compound is present in the solvent system between about 0.1-10 wt %.

In one or more embodiments related to the ninth aspect, the w/w ratio of the monohydric primary alcohol and the optionally lower alkyl end-capped oligomeric alkylene glycol is between about 1.0 and 2.4, or is between about 1.0 and 2.3. Exemplary monohydric alcohols have been previously described. For example, in one or more embodiments, the monohydric alcohol is of the form R—OH, where R is selected from methyl, ethyl, propyl, butyl, and pentyl. In one or more additional embodiments, the monohydric alcohol is represented by the structure C_(n)H_(2n)—OH, where n is 1, 2, 3 or 4. In a preferred embodiment of the foregoing, R is ethyl.

In one or more additional embodiments related to the ninth aspect, or its related embodiments, the monohydric primary alcohol comprises benzyl alcohol. In one or more exemplary related embodiments, the monohydric primary alcohol comprises a mixture of a C1-C6 primary aliphatic alcohol and benzyl alcohol. In one or more particular embodiments, the composition comprises ethyl alcohol and benzyl alcohol. In one or more related embodiments, the composition comprises from about 1% to about 8% by weight benzyl alcohol, or alternatively, comprises from about 2% to about 6% by weight benzyl alcohol. In yet one or more additional embodiments related to the ninth aspect, the w/w ratio of the monohydric alcohol to benzyl alcohol is in a range of about 3 to 11, or more preferably, is in a range of about 4 to 10.

In one or more additional embodiments related to the ninth aspect, the percent by weight of benzyl alcohol is less than the percent by weight of the optionally lower alkyl end-capped oligomeric alkylene glycol and is also less than the percent by weight of the fused bicylic ether having from 8-14 carbon atoms.

In one or more particular embodiments, the optionally lower alkyl end-capped oligomeric alkylene glycol is end-capped. Illustrative end capping groups include a methyl (—OCH₃) or an ethyl (—OCH₂CH₃) group.

In one or more embodiments, the optionally lower alkyl end-capped oligomeric alkylene glycol comprises from 2 to 4 ethylene oxide repeat units. In one or more particular embodiments, the optionally lower alkyl end-capped oligomeric alkylene glycol comprises 2 ethylene oxide repeat units. In yet a further embodiment, the optionally lower alkyl end-capped oligomeric alkylene glycol is end-capped and is diethylene glycol monoethyl ether (DEGMEE).

In one or more further embodiments, e.g., related to the ninth aspect, the optionally lower alkyl end-capped oligomeric alkylene glycol is a non-end capped oligomeric ethylene glycol having a number average molecular weight from 300-600 (i.e., a PEG having an average molecular weight between about 300 and 600. In one or more particular embodiments, the non-end capped oligomeric ethylene glycol has a number average molecular weight of 400.

In one or more particular embodiments, the optionally lower alkyl end-capped oligomeric alkylene glycol is either diethylene glycol monoethyl ether or is PEG (e.g., PEG 300-600). In yet a further embodiment, the composition comprises either diethylene glycol monoethyl ether or PEG (e.g., PEG 300-600) but does not comprise both.

In one or more further embodiments related to the ninth aspect (and its related embodiments), the w/w ratio of the optionally lower alkyl end-capped oligomeric alkylene glycol to the fused bicyclic ether having from 8-14 carbon atoms is in a range between about 1 and 2, or alternatively, is in a range between about 1.2 and 1.8.

In one or more specific embodiments, the w/w ratio of the optionally lower alkyl end-capped oligomeric alkylene glycol to the fused bicyclic ether having from 8-14 carbon atoms is about 1.7.

In one or more further embodiments related to the ninth aspect, the combined percent by weight of the optionally lower alkyl end-capped oligomeric alkylene glycol and the fused bicyclic ether having from 8-14 carbon atoms is from 30-50 w/w %.

In yet an additional one or more embodiments, the combined percent by weight of the optionally lower alkyl end-capped oligomeric alkylene glycol and the fused bicyclic ether having from 8-14 carbon atoms is 40 w/w %.

In one or more particular embodiments, the fused bicyclic ether having from 8-14 carbon atoms comprises two fused tetrahydrofuran rings. In yet one or more additional embodiments, the two fused tetrahydrofuran rings possess two methoxy substituents. In a preferred embodiment, the fused bicyclic ether is dimethyl isosorbide.

In yet another embodiment related to the ninth aspect or its related embodiments, the composition is absent benzyl alcohol. In yet an additional one or more further related embodiments, the composition is absent benzyl alcohol and further comprises phenoxyethanol, e.g., from 0.5 to 2.5 weight percent phenoxyethanol. In yet a further embodiment related to the foregoing, the composition is absent both benzyl alcohol and propylene carbonate, yet comprises phenoxyethanol.

In one or more additional embodiments related to at least the ninth aspect, the composition further comprising from 1 to 7 weight percent propylene carbonate.

In one or more preferred embodiments, the composition comprises an N-methyl lactam.

In one or more particular embodiments, the composition comprises N-methyl pyrrolidone. In one or more embodiments related to the foregoing, the composition comprises N-methyl pyrrolidone, and the w/w ratio of the monohydric primary alcohol and the optionally lower alkyl end-capped oligomeric alkylene glycol is between about 1.0 and 1.5. In yet one or more further embodiments, the percentage by weight of each of the monohydric primary alcohol, the optionally lower alkyl end-capped oligomeric alkylene glycol, and N-methyl pyrrolidone is from 20-30. In a preferred embodiment, the composition comprises ethanol, diethylene glycol monoethyl ether, and N-methyl pyrrolidone.

In yet an additional aspect (or tenth aspect), provided is a composition comprising a hedgehog inhibitor compound and a solvent system comprising (i) a ternary combination of low molecular weight aliphatic polyols (e.g., having molecular weights in a range from 50 to 550) having 2 or 3 hydroxyl groups and a lower alkyl end-capped oligomeric alkylene glycol in a w/w ratio of between about 1.5 and 2.4 and (ii) a fused bicyclic ether having from 8-14 carbon atoms, wherein the hedgehog inhibitor compound is present in the solvent system between about 0.1-10 wt %.

In one or more embodiments related to the tenth aspect, the ternary combination of low molecular weight aliphatic polyols comprises HOCH₂C(OH)HR′ where R′ is —CH₃ or —CH₂OH. In yet a more particular embodiment, the ternary combination of low molecular weight aliphatic polyols comprises glycerol and propylene glycol.

In one or more further embodiments, the ternary combination of low molecular weight aliphatic polyols comprises glycerol, propylene glycol and polyethylene glycol. In one or more further embodiments, the polyethylene glycol has a number average molecular weight from 300-500. In one or more particular embodiments, the w/w ratio of propylene glycol to glycerol is between 1.5 and 2.5 and the w/w ratio of polyethylene glycol to glycerol is between 1.5 and 2.5.

In one or more further embodiments related to the tenth aspect, the w/w ratio of the ternary combination of aliphatic polyols to the lower alkyl end-capped oligomeric alkylene glycol is in a range from 1.8 to 2.1. In yet one or more further embodiments, the composition comprises from about 40 to 55 percent by weight of the ternary combination of aliphatic polyols.

In yet another embodiment related to the tenth aspect, the composition is absent an aliphatic monohydric alcohol (e.g., ethanol).

In one or more additional embodiments related to the tenth aspect, the composition further comprises from about 1% to about 8%, or from about 2% to about 6% by weight benzyl alcohol.

In one or more additional embodiments related to the tenth aspect, the weight percent of benzyl alcohol is less than the weight percent of the lower alkyl end-capped oligomeric alkylene glycol and is also less than the weight percent of the fused bicylic ether having from 8-14 carbon atoms.

In one or more further embodiments, the lower alkyl end-capped oligomeric alkylene glycol is end-capped with a methyl or an ethyl group. In one or more particular embodiments, the lower alkyl end-capped oligomeric alkylene glycol comprises 2 ethylene oxide repeat units. In a preferred embodiment, the lower alkyl end-capped oligomeric alkylene glycol is diethylene glycol monoethyl ether (DEGMEE).

In one or more further embodiments directed to at least the tenth aspect, the w/w ratio of the lower alkyl end-capped oligomeric alkylene glycol to the fused bicyclic ether having from 8-14 carbon atoms is in a range between about 1 and 2, or is more preferably in a range between about 1.2 and 1.8.

In one or more additional embodiments related to at least the tenth aspect, the w/w ratio of the lower alkyl end-capped oligomeric alkylene glycol to the fused bicyclic ether having from 8-14 carbon atoms is about 1.7.

In one or more further embodiments related to the tenth aspect, the combined percent by weight of the lower alkyl end-capped oligomeric alkylene glycol and the fused bicyclic ether having from 8-14 carbon atoms is from 30-50 w/w %. In a particular embodiment, the combined percent by weight of the lower alkyl end-capped oligomeric alkylene glycol and the fused bicyclic ether having from 8-14 carbon atoms is 40 w/w %.

In one or more particular embodiments related to the tenth (or ninth) aspect, the fused bicyclic ether having from 8-14 carbon atoms is dimethyl isosorbide.

In one or more embodiments related to the ninth or tenth aspects, the composition is absent a surfactant.

In one or more embodiments related to the ninth or tenth aspects, the composition is non-aqueous.

In one or more embodiments related to the ninth or tenth aspects, the composition is absent a triglyceride.

In one or more embodiments related to the ninth or tenth aspects, the composition is absent a complexing agent such as a cyclodextrin.

In one or more embodiments related to the ninth or tenth aspects, the composition is not an oil-in-water emulsion.

In one or more embodiments related to the ninth or tenth aspects, the composition is absent a hydrophobic oil.

In one or more additional embodiments related to the ninth or tenth aspects, the composition is absent a surfactant, is absent a triglyceride, is absent a complexing agent, is absent a hydrophobic oil, and is not an oil-in-water emulsion.

In yet a further embodiment related to the ninth or tenth aspects, the composition further comprising a gelling agent. In one or more embodiments, the gelling agent is hydroxypropylcellulose. In one or more related embodiments, the composition is in the form of a gel.

In one or more further embodiments related to at least the ninth and tenth aspects, the hedgehog inhibitor compound is a triazolyl-triazolone. In one or more particular embodiments, the hedgehog inhibitor compound is itraconazole or is a combination of itraconazole and patidegib.

In one or more additional embodiments related to the foregoing, the composition possesses a saturated solubility of itraconazole of from about 0.14-1.5 w/w percent, or more preferably, from about 0.25-1.0 w/w percent.

In one or more further embodiments, the itraconazole is present in the solvent system between about 0.1-5 wt %, or more preferably, is present in the solvent system between about 0.1-2 wt %.

In yet another aspect, topical delivery system is provided that is comprised of a composition as described herein. The topical delivery system can further comprise, in one embodiment, a backing member and membrane joined to define a reservoir in which the composition is contained. In one embodiment, the membrane is a non-rate controlling membrane.

In another aspect, the present invention provides a method of treating a skin cancer in a subject, the method comprising the topical administration to the skin of a subject a therapeutically effective amount of a composition comprising, consisting essentially of, or consisting of a composition or topical delivery system as described herein.

In still another aspect, a method for treating basal cell carcinoma is provided, where the method comprises providing a composition as described herein or a topical delivery system as described herein, whereby the providing comprises instructions to topically apply the composition of the system and wherein said topically applying achieves intracutaneous delivery of the hedgehog inhibitor compound in an amount sufficient for treating basal cell carcinoma, with a non-therapeutic concentration of the compound present in the blood of the subject.

In still another aspect, a method for treating basal cell carcinoma is provided, where the method comprises topically applying a composition as described herein or a topical delivery system as described herein to a subject in need thereof, whereby the topically applying achieves intracutaneous delivery of the hedgehog inhibitor compound in an amount sufficient for treating basal cell carcinoma, with a non-therapeutic concentration of the compound present in the blood of the subject.

In still another aspect, a method for preventing basal cell carcinoma in a subject at risk thereof is provided, where the method comprises topically applying a composition as described herein or a topical delivery system as described herein to a subject in need thereof, whereby the topically applying achieves intracutaneous delivery of the hedgehog inhibitor compound in an amount sufficient for treating basal cell carcinoma, with a non-therapeutic concentration of the compound present in the blood of the subject.

In yet another aspect, a method for slowing progression (i.e., controlling the growth) of basal cell carcinoma in a subject with basal cell carcinoma or at risk of basal cell carcinoma is provided, where the method comprises topically applying a composition as described herein or a topical delivery system as described herein to a subject in need thereof, whereby the topically applying achieves intracutaneous delivery of the hedgehog inhibitor compound in an amount sufficient for controlling the growth of the basal cell carcinoma, with a non-therapeutic concentration of the compound present in the blood of the subject.

In one embodiment, the subject has Gorlin syndrome.

In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following descriptions.

Additional embodiments of the present methods and compositions, and the like, will be apparent from the following description, drawings, examples, and claims. As can be appreciated from the foregoing and following description, each and every feature described herein, and each and every combination of two or more of such features, is included within the scope of the present disclosure provided that the features included in such a combination are not mutually inconsistent. In addition, any feature or combination of features may be specifically excluded from any embodiment of the present invention. Additional aspects and advantages of the present invention are set forth in the following description and claims, particularly when considered in conjunction with the accompanying examples and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a graph showing the cumulative amount of patidegib permeated across human skin in vitro, in ng/cm², as a function of time, in hours, for five exemplary topical compositions of patidegib;

FIG. 1B is a bar graph showing the amount of patidegib, in ng, at various locations in a skin sample after 48 hours of in vitro contact with five exemplary compositions of patidegib in a solvent system, where the bars correspond to amount of patidegib in the stratum corneum (dashes), epidermis (horizontal fill), dermis (diagonal fill) and receiver fluid (dots);

FIG. 2A is a graph showing the cumulative amount of patidegib permeated across human skin in vitro, in ng/cm², as a function of time, in hours, for six exemplary compositions of patidegib in a solvent system;

FIG. 2B is a bar graph showing the amount of patidegib, in ng, at various locations in a skin sample after 48 hours of in vitro contact with six exemplary compositions of patidegib in a solvent system, where the bars correspond to amount of patidegib in the stratum corneum (dashes), epidermis (horizontal fill), dermis (diagonal fill) and receiver fluid (dots);

FIG. 3A is a graph showing the cumulative amount of patidegib permeated across human skin in vitro, in ng/cm², as a function of time, in hours, for six exemplary compositions of patidegib in a solvent system; and

FIG. 3B is a bar graph showing the amount of patidegib, in ng, at various locations in a skin sample after 48 hours of in vitro contact with six exemplary compositions of patidegib in a solvent system, where the bars correspond to amount of patidegib in the stratum corneum (dashes), epidermis (horizontal fill), dermis (diagonal fill) and receiver fluid (dots).

FIG. 4 is a graph demonstrating the cumulative amount of itraconazole permeated through human skin per unit area (ng/cm²) over a 48 hour time period when evaluated at each of the following time points (hours): 0, 14, 18, 24, 26, 36, 40, 44 and 48 for representative topical formulations comprising itraconazole as described in Example 9.

FIG. 5 is a bar graph illustrating the amount of itraconazole recovered (in ng) from each skin layer after the final 48 hour time point for each of the representative formulations evaluated following a permeation/penetration experiment as described in detail in Example 9. For each test item (itraconazole formulation), data is provided from left to right along the horizontal axis for the stratum corneum, epidermis, dermis, and receiver fluid.

FIGS. 6A-6B are mean concentration-time profiles of patidegib (FIG. 6A) and its metabolite, IPI-230 (FIG. 6B) in Gottingen Minipig® plasma for the test groups (male and female results combined) treated with 40 mg/kg/day (closed circles) and 80 mg/kg/day (inverted diamonds) patidegib topically.

FIGS. 7A-7B are dose normalized C_(max) and AUC₀₋₂₄ relationships, respectively, of patidegib in Gottingen Minipig® plasma for the test groups (male and female results combined) treated with 40 mg/kg/day and 80 mg/kg/day patidegib topically, on Day 1 (closed circles), Day 14 (inverted triangles) and Day 90 (closed squares) of the study (Example 11).

DETAILED DESCRIPTION I. Definitions

Various aspects now will be described more fully hereinafter. Such aspects may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey its scope to those skilled in the art.

Where a range of values is provided, it is intended that each intervening value between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the disclosure. For example, if a range of 1 μm to 8 μm is stated, it is intended that 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, and 7 μm are also explicitly disclosed, as well as the range of values greater than or equal to 1 μm and the range of values less than or equal to 8 μm.

As used in this specification, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a “polymer” includes a single polymer as well as two or more of the same or different polymers, reference to an “excipient” includes a single excipient as well as two or more of the same or different excipients, and the like.

The compositions of the present disclosure can comprise, consist essentially of, or consist of, the components disclosed.

All percentages, parts and ratios are based upon the total weight of the topical compositions and all measurements made are at about 25° C., unless otherwise specified.

For any particular compound disclosed herein, any general or specific structure presented also encompasses all conformational isomers, regioisomers, and stereoisomers that can arise from a particular set of substituents, unless stated otherwise. Similarly, unless stated otherwise, the general or specific structure also encompasses all enantiomers, diastereomers, and other optical isomers whether in enantiomeric or racemic forms, as well as mixtures of stereoisomers, as would be recognized by a skilled artisan.

The phrase “pharmaceutically acceptable” is employed herein to refer to those compounds, salts, compositions, dosage forms, etc., which are—within the scope of sound medical judgment—suitable for use in contact with the tissues of human beings and/or other mammals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio. In some aspects, “pharmaceutically acceptable” means approved by a regulatory agency of the federal or a state government, or listed in the U.S. Pharmacopeia or other generally recognized pharmacopeia for use in mammals (e.g., animals), and more particularly, in humans.

The term “treating” is used herein, for instance, in reference to methods of treating cancer, and includes the administration of a compound or composition or topical delivery system which reduces the frequency of, or delays the onset of, symptoms of a medical condition (e.g., cancer) in a subject relative to a subject not receiving the compound or composition or topical delivery system. This can include reversing, reducing, or arresting the symptoms, clinical signs, and underlying pathology of the condition in a manner to improve or stabilize a subject's condition (e.g., regression of tumor growth). Treatment of basal cell carcinoma encompasses, for example, chronic management of the condition, such as controlling the growth of the basal cell carcinoma, reducing the tumor burden, as well as prevention.

The terms “inhibiting” or “reducing” are used in reference to methods to inhibit or to reduce tumor growth (e.g., decrease the size of a tumor) in a population as compared to a untreated control population.

“Substantially” or “essentially” means nearly totally or completely, for instance, 95% or greater, of a given quantity.

“Oligomer” or “oligomeric” as used herein refers to a chemical entity having from 2 to 13 repeat units. For example, an oligomeric alkylene glycol is having from 2 to about 13 alkylene glycol repeat units, such as ethylene oxide or propylene oxide repeat units.

The term “end-capped” as used herein refers to a terminal or endpoint of an entity such as an oligomer having ethylene oxide repeat units in which one of the terminal hydroxyl groups has been converted to a non-reactive group, such as an ether (—OR). Typically, although not necessarily, the end-capping moiety is a lower alkoxy group, such as a C₁₋₆ alkoxy group. Examples of end-capping moieties include methoxy, ethoxy, propoxy, butoxy, and the like.

“Lower alkyl” refers to an alkyl group containing from 1 to 6 carbon atoms, and may be straight chain or branched, as exemplified by methyl, ethyl, n-butyl, i-butyl, t-butyl.

A “fused bicyclic ether” refers to a fused bicyclic ring system (i.e., containing two fused aliphatic rings) comprising from 1 to 3 oxygen atoms (e.g., 1, 2 or 3) in the ring system. The fused bicyclic ether possesses no unsaturation, and may comprise from 1 to 4 additional substituents comprising atoms selected from carbon, hydrogen and oxygen. One example of a fused bicyclic ether is isosorbide dimethyl ether (synonyms include dimethyl isosorbide and 1,4:3,6-dianhydro-2,5-di-O-methyl-D-glucitol), which possesses two methoxy groups substituted on the dianhydro-D-glucitol ring system. A fused bicyclic ether having from “8-14 carbon atoms” refers to the total number of carbon atoms contained in the fused bicyclic ether including any substituents.

“Alkoxy” refers to an —O—R group, wherein R is alkyl, preferably C₁-C₆ alkyl (e.g., methoxy, ethoxy, propoxy, etc.).

A “non-aqueous” formulation generally refers to a formulation comprises less than 2% by weight water. Thus, a non-aqueous formulation may comprise trace amounts of water, however water is not added as a formulation component.

A hydrophobic oil as used herein refers to a higher fatty acid ester, oils and fats, higher fatty acids, and higher acids, where higher refers to a carbon chain of 12-28 carbon atoms.

A low molecular weight polyol refers to a polyol having a molecular weight in a range from 50 to 550. For an oligomeric polyol such as oligomeric PEG, the molecular weight is generally a number average molecular weight.

“Optional” or “optionally” means that the subsequently described circumstance may but need not necessarily occur, so that the description includes instances where the circumstance occurs and instances where it does not.

By reserving the right to proviso out or exclude any individual members of any such group, including any sub-ranges or combinations of sub-ranges within the group, that can be claimed according to a range or in any similar manner, less than the full measure of this disclosure can be claimed for any reason. Further, by reserving the right to proviso out or exclude any individual substituents, analogs, compounds, ligands, structures, or groups thereof, or any members of a claimed group, less than the full measure of this disclosure can be claimed for any reason.

All publications cited herein are hereby incorporated by reference in their entirety.

II. Topical Formulations

A topical composition for intracutaneous delivery of a hedgehog inhibitor compound is described. Hedgehog inhibitor compounds and solvent systems that together comprise the topical formulations will now be described.

A. Hedgehog Inhibitor Compounds

The Hedgehog polypeptide is a secreted protein that functions as a signaling ligand in the hedgehog pathway. Three different forms of the hedgehog protein are found in humans: Sonic hedgehog, Desert hedgehog and Indian hedgehog. Sonic hedgehog is the most prevalent hedgehog member in mammals and also is the best characterized ligand of the hedgehog family. Prior to secretion, Sonic hedgehog undergoes an intramolecular cleavage and lipid modification reaction. The lipid modified peptide is responsible for signaling activities. Inhibition of the hedgehog pathway in certain cancers has been shown to result in inhibition of tumor growth (Von Hoff D. et al., N. Engl. J. Med, 361(12):1164-72 (2009); Kim et al., Cancer Cell, 23(1):23-34 (2013)). Small molecule inhibition of hedgehog pathway activity results in cell death in a number of cancer types (Tang, et al., N. Eng. J. Med., 366 (23): 2180-2188 (2012); Kim, et al., J. of Clin. Oncol., 32: 1-7 (2014).

Hedgehog inhibitor compounds contemplated for use include, for example, those described and disclosed in U.S. Pat. Nos. 7,230,004, 7,812,164; 8,669,365, U.S. Patent Application Publication No. 2008/0287420, U.S. Patent Application Publication No. 2008/0293755 and U.S. Patent Application Publication No. 2013/0109700, the entire disclosures of which are incorporated by reference herein. Examples of other suitable hedgehog inhibitors include those described in U.S. Patent Application Publication Nos. US 2002/0006931, US 2007/0021493 and US 2007/0060546, and International Application Publication Nos. WO 2001/19800, WO 2001/26644, WO 2001/27135, WO 2001/74344, WO 2003/011219, WO 2003/088970, WO 2004/020599, WO 2005/013800, WO 2005/033288, WO 2005/032343, WO 2005/042700, WO 2006/028958, WO 2006/050351, WO 2006/078283, WO 2007/054623, WO 2007/059157, WO 2007/120827, WO 2007/131201, WO 2008/070357, WO 2008/110611, WO 2008/112913, and WO 2008/131354.

Additional examples of hedgehog inhibitors include, but are not limited to, GDC-0449 (also known as RG3616 or vismodegib) described in, e.g., Von Hoff D. et al., N. Engl. J. Med. 361(12):1164-72 (2009); Robarge K. D. et al., Bioorg Med Chem Lett., 19(19):5576-81 (2009); Rudin, C. et al., New England J. of Medicine, 361-366 (2009); BMS-833923 (also known as XL139) described in, e.g., in Siu, L. et al., J. Clin. Oncol. 28:15s (suppl; abstr 2501) (2010); LDE-225 described, e.g., in Pan S. et al., ACS Med. Chem. Lett. 1(3): 130-134 (2010); LEQ-506 described, e.g., in National Institute of Health Clinical Trial Identifier No. NCT01106508; PF-04449913 described, e.g., in National Institute of Health Clinical Trial Identifier No. NCT00953758; Hedgehog pathway antagonists disclosed in U.S. Patent Application Publication No. 2010/0286114; SMOi2-17 described, e.g., U.S. Patent Application Publication No. 2010/0093625; SANT-1 and SANT-2 described, e.g., in Rominger C. M. et al., J. Pharmacol. Exp. Ther., 329(3):995-1005 (2009); 1-piperazinyl-4-arylphthalazines or analogues thereof, described in Lucas B. S. et al., Bioorg. Med. Chem. Lett., 20(12):3618-22 (2010).

In certain embodiments, the hedgehog inhibitor is a steroidal alkaloid of the cyclopamine family.

In certain embodiments, the hedgehog inhibitor is a compound of formula (I):

or a pharmaceutically acceptable form thereof (e.g., a salt and/or solvate) thereof; wherein:

R¹ is H, alkyl, —OR, amino, sulfonamido, sulfamido, —OC(O)R⁵, —N(R⁵)C(O)R⁵, or a sugar;

R² is H, alkyl, alkenyl, alkynyl, aryl, cycloalkyl, nitrile, or heterocycloalkyl;

or R¹ and R² taken together form ═O, ═S, ═N(OR), ═N(R), ═N(NR₂), or ═C(R)₂;

R³ is H, alkyl, alkenyl, or alkynyl;

R⁴ is H, alkyl, alkenyl, alkynyl, aryl, cycloalkyl, heterocycloalkyl, aralkyl, heteroaryl, heteroaralkyl, haloalkyl, —OR, —C(O)R⁵, —CO₂R⁵, —SO₂R⁵, —C(O)N(R⁵)(R⁵), —[C(R)₂]_(q)—R⁵, —[(W)—N(R)C(O)]_(q)R⁵, —[(W)—C(O)]_(q)R⁵, —[(W)—C(O)O]_(q)R⁵, —[(W)—OC(O)]_(q)R⁵, —[(W)—SO₂]_(q)R⁵, —[(W)—N(R⁵)SO₂]_(q)R⁵, —[(W)—C(O)N(R⁵)]_(q)R⁵, —[(W)—O]_(q)R⁵, —[(W)—N(R)]_(q)R⁵, —W—NR₃ ⁺X⁻ or —[(W)—S]_(q)R⁵; wherein each W is independently for each occurrence a diradical such as an alkylene; each q is independently for each occurrence 1, 2, 3, 4, 5, or 6; and X⁻ is an anion (e.g., a halide);

each R⁵ is independently for each occurrence H, alkyl, alkenyl, alkynyl, aryl, cycloalkyl, heterocycloalkyl, aralkyl, heteroaryl, heteroaralkyl or —[C(R)₂]_(p)—R⁶; wherein p is 0-6; or any two occurrences of R⁵ on the same substituent can be taken together to form a 4-8 membered optionally substituted ring which contains 0-3 heteroatoms selected from N, O, S, and P; and

each R⁶ is independently hydroxyl, —N(R)COR, —N(R)C(O)OR, —N(R)SO₂(R), —C(O)N(R)₂, —OC(O)N(R)(R), —SO₂N(R)(R), —N(R)(R), —COOR, —C(O)N(OH)(R), —OS(O)₂OR, —S(O)₂OR, —OP(O)(OR)(OR), —NP(O)(OR)(OR), or —P(O)(OR)(OR); and

each R is independently H, alkyl, alkenyl, alkynyl, aryl, cycloalkyl or aralkyl; provided that when R², R³ are H and R⁴ is hydroxyl; R¹ cannot be hydroxyl; provided that when R², R³, and R⁴ are H; R¹ cannot be hydroxyl; and provided that when R², R³, and R⁴ are H; R¹ cannot be sugar.

In certain embodiments, R¹ is H, hydroxyl, alkoxyl, aryloxy, or amino.

In some embodiments, R¹ and R² taken together along with the carbon to which they are bonded, form ═O, ═N(OR), or ═S.

In other embodiments, R³ is H and/or R⁴ is H, alkyl, hydroxyl, aralkyl, —[C(R)₂]_(q)—R⁵, —[(W)—N(R)C(O)]_(q)R⁵, —[(W)—N(R)SO₂]_(q)R⁵, —[(W)—C(O)N(R)]_(q)R⁵, —[(W)—O]_(q)R⁵, —[(W)—C(O)]_(q)R⁵, or —[(W)—C(O)O]_(q)R⁵.

In yet other embodiments, R¹ is H or —OR, R² is H or alkyl, and R⁴ is H.

In yet other embodiments, R² is H or alkyl, R³ is H, alkyl, alkenyl, alkynyl, aryl, cycloalkyl, heterocycloalkyl, or aralkyl; and/or R⁴ is H, alkyl, aralkyl, —[(W)—N(R)C(O)]_(q)R⁵, —[(W)—N(R)SO₂]_(q)R⁵, —[(W)—C(O)N(R)]_(q)R⁵, —[(W)—O]_(q)R⁵, —[(W)—C(O)]_(q)R⁵, or —[(W)—C(O)O]_(q)R⁵.

In yet other embodiments, R¹ is sulfonamido.

Specific examples of hedgehog inhibitors include compounds, or pharmaceutically acceptable salts and/or solvates thereof, described in U.S. Pat. No. 7,812,164, incorporated by reference herein. An illustrative example of a hedgehog inhibitor is the following compound, referred to herein as patidegib, previously referred to as “saridegib” and also known in the art as IPI-926:

The hedgehog inhibitor compounds described herein can be employed in a pharmaceutically acceptable salt form, and in one embodiment, the salt form is the hydrochloride salt of Compound II, identified below as Compound II-a:

In certain other embodiments, the hedgehog inhibitor is a triazolyl-triazolone compound according to formula (or compound) III:

where R₁ is one or more independently selected halo groups substituted on the phenyl ring (i.e., the phenyl ring may comprise 1, 2, 3, 4 or 5 R₁ groups, that may be the same or different, where each R₁ is a halo group). In some embodiments, the halo group is selected from chloro, bromo and fluoro. In one or more embodiments, the phenyl ring comprises a single R₁ group that is ortho, meta or para to the attachment to the dioxolane or the dioxane moiety. In yet other embodiments, the phenyl ring comprises two R₁ groups that may be positioned in any configuration on the phenyl ring. In a preferred embodiment, the R₁ groups are the same. In further embodiments, the phenyl ring comprises three R₁ groups, or even four R₁ groups, or even five R₁ groups. In some embodiments, the R₁ groups are the same. Further in reference to Compound III, n is 0 or 1; that is to say, the oxygen containing heterocycle is either dioxane or is dioxolane. In one preferred embodiment, n is 0. The substituent attached to the triazolone ring, R₂, is typically a branched or linear lower alkyl group; examples include but are not limited to methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl.

In some embodiments of Compound (III), n is 0 and R₁ represents two chloro groups. In some embodiments, R₁ represents two chloro groups that are positioned ortho- and para- to the bond connecting the phenyl group to a 1,3-dioxolane ring. In some embodiments of Compound (III), R₂ is —CCH₃CH₂CH₃. In certain other preferred embodiments, Compound III is itraconazole (Compound III-a, (2R,4S)-rel-1-(butan-2-yl)-4-{4-[4-(4-{[(2R,4S)-2-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-ylmethyl)-1,3-dioxolan-4-yl]methoxy}phenyl)piperazin-1-yl]phenyl}-4,5-dihydro-1H-1,2,4-triazol-5-one)). Itraconazole possesses three chiral centers, and may be used in the instant topical formulations as a mixture of racemates, or in optically pure form (i.e., of any one particular stereoisomer), or as a mixture enriched in one or more of the stereoisomers. Itraconazole may also be in the form of a pharmaceutically acceptable salt. The commercially available drug (marketed as an antifungal) is provided as a stereoisomeric mixture of four stereoisomers, i.e., a mixture of two racemates, all of the stereoisomers having a cis configuration (where the hydrogen and the 2,4-dichlorophenyl group at the two chiral centers are on the same side of the dioxolane ring). Shi et al., ACS Med. Chem. Lett., 2010, 1, 155-159. In one or more embodiments, a composition or delivery system comprises itraconazole as a stereoisomeric mixture of four stereoisomers, i.e., a mixture of two racemates, all of the stereoisomers having a cis configuration.

Itraconazole is a potent antagonist of the Hedgehog (Hh) signaling pathway that acts by a mechanism distinct from its inhibitory effect on fungal sterol biosynthesis. Itraconazole appears to act on the essential Hh pathway component Smoothened (Smo) by a mechanism distinct from that of cyclopamine and other known Smo antagonists, and prevents the ciliary accumulation of Smo normally caused by Hh stimulation (Kim, J., et al., Cancer Cell., 2010 Apr. 13; 17(4): 388-399).

B. Exemplary Solvent Systems and Compositions Comprising the Solvent Systems

Solvent systems for topical administration of a hedgehog inhibitor compound having a structure exemplified by Compound I or Compound III are described. As an exemplary compound in the solvent systems, a salt form of Compound II (patidegib), the hydrochloride salt form shown as Compound II-a, was used in some of the studies. Additional studies in which another exemplary compound, itraconazole, was used, are also described below (and in the examples which follow).

In a study detailed in Example 1, five topical formulations were prepared. Ingredients in the compositions are summarized in Table 1 and in the tables presented in Example 1.

TABLE 1 Exemplary Topical Compositions Ethanol/ PG¹ benzyl isostearic phenoxy buffer³ Name Ratio DEGEE² alcohol acid ethanol (pH 7.5) HPC patidegib SS5 1.00 18.7 1.9 — — 35.6 2.0 4.4 SS6 1.50 18.4 1.8 — — 25.7 2.0 6.2 SS14 1.25 18.8 — — 0.9 31.0 2.0 5.0 SS20 1.25 — 1.9 — — 49.5 2.0 3.7 SS22 1.56 — 1.9 14.2 — — 2.0 4.4 ¹PG = propylene glycol ²DEGEE = diethylene glycol monoethyl ether ³buffer pH 7.5 comprised of boric acid (0.16< adjusted with sodium hydroxide (0.1M)

The solvent system in one embodiment comprises a binary solvent system of a monohydric alcohol having between about 1-6 carbon atoms and a polyol. In one embodiment, the monohydric alcohol is a primary alcohol selected from methanol, ethanol, 1-propanol, butanol, amyl alcohol (pentanol) and cetyl alcohol (hexadecane-1-ol). In another embodiment the monohydric alcohol is a secondary alcohol such as isopropyl alcohol, and in another embodiment the monohydric alcohol is an aliphatic secondary alcohol, e.g., a secondary alcohol lacking a ring structure. In yet another embodiment, the monohydric alcohol is one having 2-4 or 2-3 carbon atoms, and in another embodiment it is a diol with 2-4 or 2-3 carbon atoms. In one embodiment the polyol is a diol selected from ethylene glycol, propylene glycol, and 1,4-butanediol. The ratio of the monohydric alcohol to polyol is between about 0.9-1.8 or 0.9-1.7, preferably between about 0.95-1.60 or between about 1.0-1.56.

The solvent system in another embodiment is a ternary solvent system comprised of the monohydric alcohol and the polyol described above in the binary solvent system and diethylene glycol monoethyl ether (DEGEE), benzyl alcohol, or both. In this ternary system, the monohydric alcohol to polyol is between about 0.9-1.8 or about 0.9-1.7, preferably between about 0.95-1.60 or between about 1.0-1.56. When the third component is DEGEE, the ratio (w/w) of monohydric alcohol to DEGEE is within about 10-20% of the ratio (w/w) of monohydric alcohol to polyol (or diol). In another embodiment, when the third component is DEGEE, the ratio (w/w) of monohydric alcohol to DEGEE is the same as the ratio (w/w) of monohydric alcohol to polyol (or diol).

The solvent system in another embodiment is a quaternary solvent system comprised of a monohydric alcohol monohydric alcohol having between about 1-6 carbon atoms and a polyol, as described above in the binary solvent system, and diethylene glycol monoethyl ether (DEGEE), benzyl alcohol, or both, and as the fourth component, phenoxyethanol. In this quaternary solvent system, the monohydric alcohol to polyol is between about 0.9-1.8 or about 0.9-1.7, preferably between about 0.95-1.60 or between about 1.0-1.56. When the third component is DEGEE, the ratio (w/w) of monohydric alcohol having between about 1-6 carbon atoms to DEGEE is within about 10-20% of the ratio (w/w) of monohydric alcohol to polyol (or diol). In another embodiment, when the third component is DEGEE, the ratio (w/w) of monohydric alcohol to DEGEE is the same as the ratio (w/w) of monohydric alcohol to polyol (or diol). The phenoxyethanol is present in the system in an amount between about 0.01-3 wt % or between about 0.07-2 wt %.

In another embodiment, the solvent system is a quaternary solvent system comprised of (i) a monohydric alcohol having between 1-6 carbon atoms, (ii) a polyol, (iii) DEGEE, benzyl alcohol, or both, and (iv) a fatty acid comprising between about 13-22 carbon atoms or a buffer. In this embodiment of a quaternary solvent system, the monohydric alcohol, polyol and DEGEE or benzyl alcohol or both are as described above for the ternary solvent system, with the additional feature that a fatty acid comprising between about 13-22 carbon atoms or a buffer is added to the system. In embodiments where a fatty acid comprising between about 13-22 carbon atoms is included in the solvent system, the fatty acid can be, in one embodiment, a saturated fatty acid. Exemplary saturated fatty acids include myristic acid (C14), isopropylmyristic acid, palmitic acid (C16), stearic acid (C18) and arachidic acid (C22). In an exemplary embodiment, the saturated fatty acid is isostearic acid. In one embodiment, the exemplary quaternary solvent system additionally comprises phenoxyethanol, rendering the system a quinary solvent system. The phenoxyethanol is present in the system in an amount between about 0.01-3 wt % or between about 0.07-2 wt %.

The composition, in one embodiment, can comprise a substance to increase viscosity, sometimes referred to as a thickening agent or gelling agent. Exemplary agents include gums (e.g., xanthan gum, guar gum), pectins, starches, and synthetic polymers, such as polyacrylic acid and hydroxyalkylcelluloses, such as hydroxyethylcellulose, hydropropylcellulose, and hydroxypropylmethylcellulose. The amount of viscosity increasing agent in the composition can range from about 0.5-10 wt %, preferably between about 0.5-5 wt % or about 0.5-3 wt %. In one embodiment, the thickening agent is hydroxyethylcellulose, and in another embodiment is hydroxyethylcellulose with a molecular weight of between about 800,000-1,250,000 Daltons.

Using these guiding principles, the intracutaneous delivery of patidegib into human skin from the five formulations set forth in Table 1 was tested in vitro using human skin in a Franz diffusion cell. As an initial indicator of partitioning of patidegib from the test formulations into the stratum corneum, the concentration of patidegib in the receiver fluid of each Franz cell was measured by taking aliquots of receiver fluid at various time points between 14-48 hours. After the 48 hour topical application to the skin, the layers of the skin were individually analyzed for concentration of patidegib in the stratum corneum, epidermis and dermis to assess intracutaneous delivery. The results are shown in FIGS. 1A-1B.

FIG. 1A shows the cumulative amount of patidegib permeated across human skin in vitro, in ng/cm², as a function of time, in hours, for the five compositions of patidegib in the exemplary solvent systems set forth in Table 1. The formulations identified as SS5 (open squares), SS6 (closed triangles), SS20 (x symbols) and SS14 (closed diamonds) each provided a cumulative amount of patidegib of at least about 250 ng/cm² in 24 hours. Two of the formulations, SS20 (x symbols) and SS14 (closed diamonds), achieved a cumulative amount of patidegib of at least about 500 ng/cm² in 36 hours. The formulation identified as SS14 achieved a cumulative amount of patidegib of at least about 1000 ng/cm² in 36 hours. The non-aqueous formulation, SS22 (open diamonds), had the lowest flux of patidegib of the formulations tested, yet provided a cumulative amount delivered across the skin of about 250 ng/cm² in 40 hours.

The desired topical formulation is one that achieves partitioning of the hedgehog inhibitor compound from the topical formulation into the stratum corneum, diffusion across the stratum corneum, and retention in the epidermis and/or dermis. Thus, to assess the ability of the formulations to achieve intracutaneous delivery rather than transdermal delivery, the concentration of hedgehog inhibitor compound in the stratum corneum, epidermis and dermis was measured after 48 hours topical exposure to the test formulations. Results of the analysis of the layers of the skin for concentration of patidegib are shown in FIG. 1B. The amount of patidegib delivered to the dermis (bars with diagonal fill) was highest for the formulations identified as SS6 and SS14, which each provided greater than 5000 ng patidegib to the dermis after 48 hours of topical application. The formulation identified as SS22 delivered greater than 7000 ng of patidegib to the epidermis (bars with horizontal fill) after 48 hours of contact with the skin.

Accordingly, in one embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis or the epidermis and dermis combined that exceeds the amount of patidegib in the stratum corneum. In another embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis, or the epidermis and dermis combined that exceeds by at least about 15%, 25% or 40% the amount of patidegib in the stratum corneum. In another embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis, or the epidermis and dermis combined that exceeds by at least about 150%, 200%, 300%, 350% or 400% the amount of patidegib in the receiver fluid. In another embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis, or the epidermis and dermis combined that is at least about 1.5, 2, 3, 3.5, 4 or 5 fold greater than the amount of patidegib in the receiver fluid.

The drug in each layer of the skin is tabulated in Table 2 in concentration units of micromolar.

TABLE 2 Concentration of patidegib (μM) in each of the stratum corneum, epidermis and dermis 48 hours after topical application. Concentration of Concentration of Concentration of patidegib (μM) in patidegib (μM) in patidegib (μM) in Formulation stratum corneum. epidermis dermis SS5 17080 1233 445 SS6 12593 1039 629 SS14 13238 1851 823 SS20 6588 1057 521 SS22 12880 2425 367

The half maximal effective concentration of patidegib for inhibition of cellular hedgehog pathway is 0.007 μM (Tremblay et al., J. Med. Chem., 52(14):4400-44118 (2009)). The formulations identified herein as SS5, SS6, SS14, SS20 and SS22 each provided for delivery of patidegib to the epidermis or dermis in an amount sufficient for therapy; that is, in one embodiment, an amount that provides a half-maximal effective concentration in the dermis, epidermis or combined dermis and epidermis within about 24 hours after topical application of the composition.

As mentioned above, the compound is included in the composition in an amount between about 0.1-10 wt %, or between about 1-10 wt %, alternatively between about 2-8 wt % or about 3-7 wt %. It will be appreciated that adjustments to the amount of compound added may vary according to the potency of the compound, although the weight percent of compound in the final formulation will typically be within the stated ranges.

In another study, detailed in Example 2, additional topical compositions were prepared and the delivery of patidegib from each was studied in vitro. The topical compositions of this study were variations of the formulations identified above as SS14 and SS22, which are included in Table 3 below for ease of reference.

TABLE 3 Exemplary Topical Compositions Aqueous Formulations Non-aqueous Formulations SS14 SS14.10 SS14.19 SS22 SS22.7 SS22.9 wt % wt % wt % wt % wt % wt % ethanol 23.5 7.4 — 47.3  — — isopropyl alcohol — — — — 49.1 49.5 propylene glycol 18.8 4.9 — 30.3  31.4 — benzyl alcohol — — — 1.9 — — DEGEE* 18.8 9.8 — isostearic acid — — — 14.2  16.7 24.7 isopropyl myristate — — — — — 23.7 phenoxyethanol  0.9 1.0 1.0 buffer 31.0 — — — — — deionized water — 74.2  96.9  — — — hydroxypropyl cellulose  2.0 2.0 2.0 2.0  2.0  2.0 patidegib  5.0  0.75 0.1 4.4  0.75  0.1 Ratio monohydric alcohol/diol  1.25  1.51 0   1.6  1.6 0  *DEGEE = diethylene glycol monoethyl ether (Transcutol ® P)

The intracutaneous delivery of patidegib from the formulations set forth in Table 3 was tested in vitro using human skin. As an initial indicator of partitioning of patidegib from the formulation into the stratum corneum, the concentration of patidegib in the receiver fluid of the Franz cell was measured by taking aliquots of receiver fluid at various time points between 14-48 hours. After the 48 hour topical application to the skin, the layers of the skin were analyzed for drug concentration to measure intracutaneous delivery. The results are shown in FIGS. 2A-2B. FIG. 2A shows the cumulative amount of patidegib permeated across human skin in vitro, in ng/cm², as a function of time, in hours. The non-aqueous formulation SS22 (open diamonds) and the aqueous formulation SS14 (closed diamonds) achieved the highest permeation of patidegib with at least about 500 ng/cm² in 24 hours and at least about 1000 ng/cm² in 36 hours. The study reveals that decreasing the concentration of hedgehog inhibitor compound decreases the cumulative amount delivered across the skin in both the aqueous and non-aqueous formulations (e.g., compare SS22.7 (non-aqueous, closed triangles) and SS14.10 (aqueous, open triangles)). Formulations with no diol, and thus a ratio of monohydric alcohol to diol of zero, and with 0.1 wt % patidegib had the lowest amount of patidegib delivered across the skin (e.g., SS22.9 (open circles) and SS14.19 (closed circles)).

At the end of the 48 hour in vitro permeation investigation, the skin was removed from the Franz diffusion cells and analyzed for patidegib concentration in the layers of the skin. The results are shown in FIG. 2B, where the bars for each formulation correspond to stratum corneum (dashes), epidermis (horizontal fill), dermis (diagonal fill) and receiver fluid (dots). The amount of patidegib delivered to the dermis (bars with diagonal fill) was highest for the formulations identified as SS14 and SS22, which each provided greater than 2900 ng of patidegib to the dermis after 48 hours of topical application. The formulation identified as SS22 delivered greater than 5000 ng of patidegib to the epidermis (bars with horizontal fill) after 48 hours of contact with the skin. The formulations with less than 1 wt % drug compound (SS14.10, SS14.19, SS22.7 and SS22.9) delivered less than about 1000 ng of drug to the epidermis or dermis after 48 hour topical application.

The drug in each layer of the skin is tabulated in Table 4 in concentration units of micromolar (μM).

TABLE 4 Concentration of patidegib (μM) in each of the stratum corneum, epidermis and dermis 48 hours after topical application. Concentra- Concentra- Concentra- Concentra- tion of tion of tion of tion of patidegib patidegib patidegib Formu- patidegib (μM) in (μM) in (μM) in lation (% w/w) Stratum corneum epidermis dermis SS14 4.97 37819 758 341 SS14.10 0.75 2687 315 50 SS14.19 0.10 215 35 5 SS22 4.35 51911 2458 349 SS22.7 0.75 1538 287 53 SS22.9 0.10 459 26 9

Accordingly, in one embodiment, the topical composition is one where the hedgehog inhibitor compound has a saturation solubility in the solvent system of between about 0.1-10 wt %, alternatively between about 2.5-8 wt %, and the solvent system comprises between about 15-60 wt % ethanol and between about 10-50 wt % propylene glycol. In another embodiment, the hedgehog inhibitor compound has a saturation solubility in the solvent system of between about 0.1-10 wt % or between about 2.5-8 wt % and is present in the composition in an amount between about 0.1-10 wt % or between about 2-8 wt %, or between about 2.5-7 wt %, or between about 2.8-7.5 or between about 3.0-7.0 wt %.

In another embodiment, the concentration of hedgehog inhibitor compound is between about 0.1-10 wt % or between about 2-8 wt %, between about 2.5-7 wt %, between about 2.8-7.5 or between about 3.0-7.0 wt %.

In another study, detailed in Example 3, the formulations identified as SS14 and SS22 were prepared with lower amount of patidegib and tested in vitro using human skin in a Franz diffusion cell. The aqueous formulation SS14 comprises of about 5 wt % patidegib and two comparative formulations were prepared that had 0.75 wt % (SS14D2) and 0.1 wt % (SS14D1) patidegib. The non-aqueous formulation SS22 comprises about 4.4 wt % patidegib and two comparative formulations were prepared that had 0.75 wt % (SS22D2) and 0.1 wt % (SS14D1) patidegib. The compositions are set forth in Example 3.

As an initial indicator of partitioning of patidegib from the formulation into the stratum corneum, the concentration of patidegib in the receiver fluid of the Franz cell was measured by taking aliquots of receiver fluid at various time points between 14-48 hours. After the 48 hour topical application to the skin, the layers of the skin were analyzed for drug concentration to measure intracutaneous delivery. The results are shown in FIGS. 3A-3B. FIG. 3A shows the cumulative amount of patidegib permeated across human skin in vitro, in ng/cm², as a function of time, in hours. The non-aqueous formulation SS22 (open diamonds) achieved the highest cumulative amount of patidegib permeated across the skin, with at least about 750 ng/cm² in 24 hours and at least about 1000 ng/cm² in 36 hours. The aqueous formulations SS14 (closed diamonds), SS14D1 (closed circles) and SS14D2 (closed squares) yielded a higher cumulative amount of patidegib permeated across the skin relative to the non-aqueous formulations with 0.75 wt % and 0.1 wt % patidegib (respectively, SS22D2, open squares and SS22D1, open circles). The study confirms the results observed in Examples 1 and 2 that the topical compositions with at least about 2 wt % drug compound, preferably at least about 2.5 wt % drug compound in a solvent system with a monohydric alcohol and a diol in a ratio of between about 1.0-1.8 or 1.2-1.6 provide a topical composition that when applied to the skin of a subject in need delivers a therapeutically effective amount at times between 10-60 hours after topical application, or at times of 10-50 hours, or 12-48 hours.

At the end of the 48 hour in vitro permeation investigation, the skin was removed from the Franz diffusion cells and analyzed for patidegib concentration in the layers of the skin. The results are shown in FIG. 3B, where the bars for each formulation correspond to stratum corneum (dashes), epidermis (horizontal fill), dermis (diagonal fill) and receiver fluid (dots). The amount of patidegib delivered to the dermis (bars with diagonal fill) was highest for the formulations identified as SS14 and SS22, which each provided greater than 3000 ng patidegib to the dermis after 48 hours of topical application. The formulation identified as SS22 delivered more drug to the dermis (bars with diagonal fill) than the epidermis (bars with horizontal fill) after 48 hours of contact with the skin. The formulations with less than 1 wt % drug compound (SS14D1, SS14D2, SS22D1 and SS22D2) delivered less than about 1000 ng of drug to the dermis after 48 hours topical application.

Accordingly, in one embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis or the epidermis and dermis combined that exceeds the amount of patidegib in the stratum corneum. In another embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis, or the epidermis and dermis combined that exceeds by at least about 15%, 25% or 40% the amount of patidegib in the stratum corneum. In another embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis, or the epidermis and dermis combined that exceeds by at least about 150%, 200%, 300%, 350% or 400% the amount of patidegib in the receiver fluid. In another embodiment, a topical formulation of patidegib is provided that achieves after 24 hours or after 48 hours of topical application in vitro an amount of patidegib in the epidermis, the dermis, or the epidermis and dermis combined that is at least about 1.5, 2, 3, 3.5, 4 or 5 fold greater than the amount of patidegib in the receiver fluid.

The drug in each layer of the skin is tabulated in Table 5 in concentration units of micromolar (μM).

TABLE 5 Concentration of patidegib (μM) in each of the stratum corneum, epidermis and dermis 48 hours after topical application. Concentra- Concentra- Concentra- Concentra- tion of tion of tion of tion of patidegib patidegib patidegib Formu- patidegib (μM) in (μM) in (μM) in lation (% w/w) Stratum corneum epidermis dermis SS14 4.97 16226 1470 401 SS14D1 0.10 553 247 35 SS14D2 0.75 3245 534 81 SS22 4.35 7329 1093 415 SS22D1 0.10 286 49 5 SS22D2 0.75 3118 597 107

The stability of several exemplary formulations was studied, as detailed in Example 4. The formulations detailed in Example 1 were stored for four weeks storage at 25° C. and at 40° C. and stability was assessed by analyzing the formulations for patidegib content. The results showed that the formulations were stable at room temperature (20-25° C.) and up to 40° C. for at least about 4 weeks, as evidenced by no degradation of patidegib. Accordingly, in one embodiment, compositions are provided that are stable, as evidenced by the patidegib content being between 95-105% of the theoretical patidegib content and/or the patidegib content at time zero (t=0), at room temperature.

In one embodiment, the formulation is an alcoholic solution. In such a formulation, the carrier is typically an admixture of monohydroxy alcohols and polyols. The formulation may optionally contain at least one penetration enhancer. Examples of suitable monohydroxy alcohols include, for example, ethanol, propanol, butanol and benzyl alcohol. Reference herein to “ethanol” includes absolute alcohol, as well as “alcohol USP” and all denatured forms of 95% ethanol. As used herein, the term “propanol” refers to all isomeric forms, including n-propanol and isopropanol, and the term “butanol” refers to all isomeric forms, including, for example, n-butanol, iso-butanol and sec-butanol. In one embodiment, the alcohol is selected from the group comprising ethanol, isopropyl alcohol, and benzyl alcohol, with ethanol being particularly useful.

Examples of suitable polyols include, for example, propylene glycol, dipropylene glycol, hexylene glycol, 1,3-butylene glycol, liquid polyethylene glycols, such as polyethylene glycol200 (PEG-200) and polyethylene glycol400 (PEG-400). A particularly useful polyol is propylene glycol.

For those formulations that are alcoholic solutions or aqueous-alcoholic solutions, the polyol will typically be present in the quantity of from about 0 to about 80% w/w, more typically about 10 to about 25% w/w. The monohydroxy alcohol will be present in the quantity of about 10 to about 99.9% w/w, more typically from about 40 to about 90% w/w. One example of such an alcoholic solution is a formulation containing about 1% w/v of Compound, about 10 to 30% w/w of a polyol, and about 40 to about 90% w/w of a monohydroxy alcohol.

Minor amounts of water can also be included in the formulation. Optionally a penetration enhancer may be incorporated into these alcoholic solutions. In one embodiment, the formulation contains from about 10% to about 25% (w/w) of a polyol, from about 50% to about 70% (w/w) of a monohydroxy alcohol and from about 1% to about 30% (w/w) of a penetration enhancer. In a second embodiment, the formulation contains from about 10% to about 25% (w/w) of a polyol selected from the group consisting of propylene glycol, dipropylene glycol, hexylene glycol, 1,3-butylene glycol, polyethylene glycol, and glycerol, from about 50% to about 70% (w/w) of a monohydroxy alcohol selected from the group consisting of ethanol, isopropyl alcohol and benzyl alcohol and from about 1% to about 30% (w/w) of a penetration enhancer selected from the group consisting of isopropyl myristate, cyclopentadecanolide and propylene glycol dicaprylate/dicaprate. In a more specific embodiment, the formulation contains from about 10% to about 25% (w/w) of propylene glycol, from about 50% to about 70% (w/w) of ethanol, and from about 1% to about 30% (w/w) of isopropyl myristate. More specifically, the formulation contains about 0.5 to about 3 w/v % of Compound, about 20% (w/w) of a propylene glycol, about 60% (w/w) of ethanol and about 20% (w/w) of isopropyl myristate.

Additional studies were conducted on exemplary topical formulations comprising the hedgehog inhibitor, itraconazole. Since itraconazole is a poorly water soluble drug, solubility studies were initially conducted to assess compound solubility in a variety of solvents. For ease of reference, the following formulation descriptions are described in the context of itraconazole as the hedgehog inhibitor compound, although any suitable hedgehog inhibitor compound, in particular those having structural and physicochemical properties similar to itraconazole may be used. Following initial screening experiments, an initial set of 13 preliminarily optimized formulations was prepared comprising various combinations of solvents and system components as described in Example 6. The combination of solvents selected for the initially optimized formulations were determined based upon solubility of the hedgehog inhibitor compound, e.g., itraconazole, stability of drug in the formulation upon storage, solvent compatibility. An additional consideration is skin permeability to achieve a localized skin effect with minimal or no systemic absorption (to be described in greater detail below). The solvent systems explored in Example 6 demonstrated acceptable solvent compatibility and drug stability results, and were then reformulated as non-aqueous gels for topical administration. Formulations for topical delivery may be in any form suitable for application to the skin, e.g., may be in the form of liquids, gels, ointments, creams, aerosols, and the like.

Based upon extensive screening studies, certain features of preferred topical formulations were determined. Topical formulations for administering a hedgehog inhibitor compound comprise a solvent system as follows. In one or more embodiments, the solvent system comprises an aliphatic monohydric alcohol having between 1-6 carbon atoms and a lower alkyl end-capped oligomeric alkylene glycol in a w/w ratio of between about 0.8 and 2.6. Suitable monohydric alcohols are as described above. For example, in one or more embodiments, the monohydric alcohol is a primary aliphatic alcohol selected from methanol, ethanol, 1-propanol, butanol, amyl alcohol (pentanol) and hexanol. Alternatively, the monohydric alcohol is a secondary alcohol such as isopropyl alcohol, or sec-butyl alcohol. In yet another embodiment, the monohydric alcohol is one having 2-4 or 2-3 carbon atoms. Exemplary solvent systems are at least ternary solvent systems comprising three different solvents each present in the solvent system in a w/w percentage greater than 10 weight percent. Thus, in reference to formulations directed to the exemplary hedgehog inhibitor, itraconazole, a binary solvent system, or a ternary solvent system, or a quaternary solvent system is one in which only two solvents, or only three solvents, or only four solvents, respectively, is present in an amount greater than 10 w/w percent. The w/w ratio of monohydric alcohol to lower alkyl end-capped oligomeric alkylene glycol is typically between 0.8 and 2.6, or is preferably between about 1.0 and 2.4, or more preferably from 1.0 and 2.3. Exemplary w/w ratios include 0.85, 0.90, 0.95, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, and 2.5, including any and all ranges in between any two of the foregoing values.

One illustrative lower alkyl end-capped oligomeric alkylene glycol suitable for use in the instant compositions (with any of the hedgehog inhibitor compounds disclosed herein) is diethylene glycol monoethyl ether (DEGEE). In one or more embodiments, the lower alkyl end-capped oligomeric alkylene glycol is end-capped with a lower alkyl group, i.e., an aliphatic C1-C6 group, modifying the terminal hydroxyl group. In this embodiment, the oligomeric alkylene glycol is end-capped with a methoxy, ethoxy, propyloxy, butoxy, pentoxy, or hexoxy group. The oligomeric alkylene glycol comprises from 2 to 13 alkylene glycol repeat units. Illustrative alkylene glycol repeat units include, for example, ethylene oxide (—CH₂CH₂O—)_(n) and propylene oxide (—CH₂CCHCH₃O—)_(n) repeat units, where n is selected from 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 13. A preferred oligomeric alkylene glycol contains ethylene oxide repeats. In one or more embodiments, the lower alkyl end-capped oligomeric alkylene glycol is diethylene glycol HO—(CH₂CH₂O)₂—R, where R is a lower alkyl group. Preferred lower alkyl end-capping groups, R are ethyl and methyl.

In some embodiments, a ternary solvent system comprises an aliphatic monohydric alcohol having between 1-6 carbon atoms and a non-end-capped oligomeric alkylene glycol (instead of a lower alkyl end-capped oligomeric alkylene glycol) in a w/w ratio of between about 0.8 and 2.6. Representative non-end capped oligomeric alkylene glycols include diols such as oligomeric PEG, and oligomeric polypropylene glycol. See, for example, formulation SS40-I or IG. As described above, an oligomeric alkylene glycol comprises from 2 to 13 alkylene glycol repeat units. Illustrative alkylene glycol repeat units include ethylene oxide (—CH₂CH₂O—)_(n) and propylene oxide (—CH₂CH₂CH₂O—)_(n) repeat units, where n is selected from 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 13. A preferred oligomeric alkylene glycol contains ethylene oxide repeats. In one or more embodiments, the non-end capped oligomeric alkylene glycol is oligomeric PEG. The oligomeric PEG typically possesses a number average molecular weight between about 300 and 600, or between about 300 and 500. A preferred oligomeric PEG is PEG-400, having a number average molecular weight of 400 (M_(n) 380-420). While oligomeric PEGs having a small number of monomer repeats may be provided as monodisperse compounds, typically, oligomeric PEGs having 5 to 13 repeat units are provided as polydisperse compounds, where the molecular weight provided is a number average molecular weight unless otherwise indicated. Oligomeric PEGs, both end-capped and non-end capped are commercially available. Representative amounts of an end-capped oligomeric alkylene glycol as described herein apply equally to formulations in which the end-capped oligomeric alkylene glycol (e.g., DEGMEE) is replaced by a non-end capped oligomeric alkyelene glycol such as PEG.

The ternary solvent systems described above further comprise a fused bicyclic ether having from 8-14 carbon atoms, where the number of carbon atoms refers to the total number of carbon atoms including any substituents. Generally, the fused bicyclic ether contains from 1 to 3 oxygen atoms (e.g., 1, 2 or 3) in the bicyclic ring system (i.e., fused oxacycles). Illustrative fused bicyclic systems include bicyclo [3.3.0] and [4.3.0] systems. The fused bicyclic ether possesses no unsaturation (i.e., is saturated), and may comprise from 1 to 4 substituents covalently attached to the bicyclic ring system, where the substituents are moieties that only contain atoms selected from carbon, hydrogen and oxygen. Illustrative substituents include alkyl groups, lower alkoxy groups, and hydroxyl groups. Representative fused bicyclic ethers include dianhydro-D-glucucitol, isosorbide dimethyl ether (synonyms include dimethyl isosorbide and 1,4:3,6-dianhydro-2,5-di-O-methyl-D-glucitol), which possesses two methoxy groups substituted on the dianhydro-D-glucitol ring system, and isosorbide diethyl ether.

In one or more embodiments, the w/w ratio of the lower alkyl end-capped oligomeric alkylene glycol to the fused bicyclic ether having from 8-14 carbon atoms is in a range between about 1 and 2.4, or between about 1 and 2, or preferably between about 1.2 and 1.8, or in some instances, is about 1.7. Exemplary w/w ratios include 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, and 2.3, including any and all ranges in between any two of the foregoing values.

In one or more embodiments, the composition comprises from about 70 w/w % to about 16 w/w % of an aliphatic monohydric primary alcohol, or from about 65 w/w % to about 18 w/w %, or preferably from about 60 w/w % to about 20 w/w % of an aliphatic monohydric primary alcohol. In the event that the composition additionally comprises a non-aliphatic monohydric primary alcohol such as benzyl alcohol, the total w/w percent of monohydric primary alcohol in the composition will increase accordingly. When present in the formulations, benzyl alcohol is typically present at a w/w percent that is less than ten percent. Thus, the above w/w percentages for total w/w percent monohydric primary alcohol will increase accordingly: 80 w/w % to about 26 w/w % of monohydric primary alcohol, or from about 75 w/w % to about 28 w/w %, or preferably from about 70 w/w % to about 30 w/w % monohydric primary alcohol. These representative w/w percentages are considered to be disclosed in combination with any of the other illustrative w/w percentages of additional composition components described herein and/or disclosed in combination with any one or more of the w/w percentages disclosed herein.

In one or more alternative embodiments, e.g., when the solvent system does not contain an N-substituted lactam, the composition comprises from about 70 w/w % to about 30 w/w % of an aliphatic monohydric primary alcohol, or from about 65 w/w % to about 35 w/w %, or preferably from about 60 w/w % to about 40 w/w % of an aliphatic monohydric primary alcohol. In the event that the composition additionally comprises a non-aliphatic monohydric primary alcohol such as benzyl alcohol, the total w/w percent of monohydric primary alcohol in the composition will increase accordingly. These representative w/w percentages are considered to be disclosed in combination with any of the other illustrative w/w percentages of additional composition components described herein and/or disclosed in combination with any one or more of the w/w percentages or ranges disclosed herein.

In one or more additional embodiments, the composition comprises from about 16 w/w % to about 35 w/w %, or from about 20 w/w % to about 30 w/w % of the lower alkyl end-capped oligomeric alkylene glycol. A representative about of the lower alkyl end-capped oligomeric alkylene glycol is about 25 w/w %. These representative w/w percentages are considered to be disclosed in combination with any of the other illustrative w/w percentages of additional composition components described herein and/or disclosed in combination with any one or more of the w/w percentages or ranges disclosed herein.

In one or more embodiments, the combined percent by weight of the lower alkyl end-capped oligomeric alkylene glycol and the fused bicyclic ether having from 8-14 carbon atoms is from 30-50 w/w %. In certain representative formulations, the combined percent by weight of the optionally lower alkyl end-capped oligomeric alkylene glycol and the fused bicyclic ether having from 8-14 carbon atoms is 40 w/w %.

In further exemplary embodiments, the topical formulation comprises from about 7 w/w % to about 25 w/w %, or from about 10 w/w % to about 20 w/w % of a fused bicyclic ether having from 8-14 carbon atoms. In one or more preferred embodiments, the w/w percent of the fused bicyclic ether having from 8-14 carbon atoms, e.g., dimethyl isosorbide, is less than the w/w percent of both the monohydric primary alcohol and the lower alkyl end-capped oligomeric alkylene glycol (e.g., DEGMEE). In one or more embodiments, the w/w percent of the fused bicyclic ether having from 8-14 carbon atoms is about 15 percent by weight.

In certain representative formulations, the ternary solvent system (i.e., composed of three solvents each present in greater than 10 percent by weight) as described above consists essentially of ethanol, diethylene glycol monoethyl ether, and dimethyl isosorbide. See, for example, compositions SS-37I (or IG, where G refers to gel) and SS-38I (or IG).

In an alternative illustrative formulation, the ternary solvent system (i.e., composed of three solvents each present in greater than 10 percent by weight) as described above consists essentially of ethanol, oligomeric polyethylene glycol, and dimethyl isosorbide. See, for example, composition SS-40I (or IG, where G refers to gel).

Generally, preferred compositions comprising itraconazole possesses a saturated solubility of itraconazole from about 0.14-1.5 w/w percent, or more preferably, from about 0.25-1.0 w/w percent.

One solvent suitable for enhancing the solubility of itraconazole in topical formulations is N-methyl-2-pyrrolidone (“N-methyl pyrrolidone or NMP”). As noted in Example 6, itraconazole possesses a saturated solubility in N-methyl pyrrolidone of 7.65% w/w. Thus, certain topical formulations of itraconazole comprise an N-substituted lactam having 5-ring atoms, 6-ring atoms or 7-ring atoms. In certain embodiments, the nitrogen atom of the lactam is substituted with a methyl or with an ethyl group (i.e., is an N-methyl or is an N-ethyl lactam). A preferred lactam is N-methyl pyrrolidone. See, e.g., formulation SS43-I or IG.

In certain formulations, the solvent system is a quaternary solvent system comprising four different solvents each present in the solvent system in a w/w percentage greater than 10 weight percent. Representative quaternary solvent systems include as one of the solvents an N-substituted lactam. Generally, such quaternary solvent systems include a monohydric primary alcohol, a lower alkyl end-capped oligomeric alkylene glycol, a fused bicyclic ether having from 8-14 carbon atoms, and an N-substituted lactam as previously described. In one or more embodiments of a quaternary solvent system, the w/w ratio of the monohydric primary alcohol and the lower alkyl end-capped oligomeric alkylene glycol is between about 0.6 and 1.5, or is between about 0.8 and 1.4, or is between about 0.9 and 1.3, or is between about 1.0 and 1.5. In yet one or more further embodiments, the percentage by weight of each of the monohydric primary alcohol, the lower alkyl end-capped oligomeric alkylene glycol, and N-vinyl pyrrolidone is from about 20-30. An exemplary quaternary solvent system consists essentially of ethanol, diethylene glycol monoethyl ether, dimethyl isosorbide, and N-methyl pyrrolidone. In one or more embodiments of a quaternary solvent system, the percent by weight of the fused bicyclic ether having from 8-14 carbon atoms is less than that of the monohydric primary alcohol, the lower alkyl end-capped oligomeric alkylene glycol, and the N-substituted lactam. Representative quaternary solvent systems comprise from about 11 w/w % to about 50 w/w %, or from about 15 w/w % to about 45 w/w %, or even from about 20 w/w % to about 35 w/w % of the N-substituted lactam. In a preferred formulation, the w/w percent of N-methyl pyrrolidone in the composition is about 25. As in all instances herein, the representative w/w percentages are considered to be disclosed in combination with any of the other illustrative w/w percentages of additional composition components described herein and/or disclosed in combination with any one or more of the w/w percentages or ranges disclosed herein. In one or more embodiments of a quaternary solvent system comprising an N-substituted lactam, the solvent system contains from about 40 w/w % to about 16 w/w % of an aliphatic monohydric primary alcohol, or from about 17 w/w % to about 35 w/w %, or preferably from about 18 w/w % to about 30 w/w % of an aliphatic monohydric primary alcohol.

An additional exemplary solvent system for topically administering a hedgehog inhibitor compound such as itraconazole comprises (i) a ternary combination of low molecular weight aliphatic polyols having molecular weights ranging from 50 to 550), where the polyols possess 2 or 3 hydroxyl groups, and a lower alkyl end-capped oligomeric alkylene glycol as described above in a w/w ratio of between about 1.5 and 2.4 and (ii) a fused bicyclic ether having from 8-14 carbon atoms (as described above). In certain embodiments of the foregoing, the solvent system is absent an aliphatic monohydric alcohol such as ethanol.

Suitable aliphatic diols and triols include, for example, propylene glycol, dipropylene glycol, hexylene glycol, 1,3-butylene glycol, liquid polyethylene glycols, such as polyethylene glycol200 (PEG-200) and polyethylene glycol400 (PEG-400), glycerol, trimethylolpropane, sorbitol and pentaerythritol. In one or more embodiments, the ternary combination contains two low molecular weight aliphatic polyols each containing 2-4 carbon atoms. In certain embodiments, the ternary combination contains two low molecular weight aliphatic polyols each containing three carbon atoms. In a particular embodiment, the ternary combination comprises HOCH₂C(OH)HR′ where R′ is —CH₃ or —CH₂OH. In certain embodiments, the ternary combination comprises glycerol and propylene glycol. In other embodiments, the ternary combination further comprises a polyethylene glycol, e.g., having a number average molecular weight from 300-500. In some embodiments, the w/w ratio of the ternary combination of aliphatic polyols to the lower alkyl end-capped oligomeric alkylene glycol is in a range from 1.8 to 2.1. For example, the ternary combination of aliphatic polyols is present in the composition at a combined w/w percent between about 35 and 60, or between about 40 and 55. In one or more further representative embodiments, w/w ratio of propylene glycol to glycerol is between 1.5 and 2.5, and the w/w ratio of polyethylene glycol to glycerol is between 1.5 and 2.5. A representative formulation is SS-50I or IG.

The instant formulations, and in particular, those particularly suited for administration of itraconazole, may, as described previously, further comprise benzyl alcohol. Benzyl alcohol, while not an aliphatic primary alcohol, is a primary alcohol. Thus, in one or more embodiments, the monohydric alcohol component comprises, in addition to an aliphatic monohydric primary alcohol, the primary alcohol benzyl alcohol. When present in the formulations, benzyl alcohol is typically present at a w/w percent that is less than ten percent. Illustrative amounts of benzyl alcohol include 1 w/w %, 2 w/w %, 3 w/w %, 4 w/w %, 5 w/w %, 6 w/w %, 7 w/w %, 8 w/w %, and 9 w/w %. An exemplary about of benzyl alcohol is 5 w/w percent. The addition of up to ten w/w percent benzyl alcohol can be effective in increasing the concentration of itraconazole in the formulations. In some embodiments, the formulation does not contain benzyl alcohol but does contain phenoxyethanol. In other embodiments, the formulation does contain benzyl alcohol but does not contain phenoxyethanol, a preservative. When contained in the instant formulations, the amount of phenoxyethanol is generally from about 0.01 w/w % to about 5 w/w %, or is from about 0.5 w/w % to about 3 w/w %, or is even present in an amount between about 0.07-2 wt %. Illustrative amounts of phenoxyethanol include the following percentages by weight: 0.1, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0.

A hedgehog inhibitor formulation, e.g., comprising itraconazole or patidegib, may additionally contain small amounts, e.g., less than about 10 w/w percent, of one or more additional additives, excipients, stabilizers, solvents, buffers, anti-oxidants, gel forming agents, preservatives, or the like. For example, in one or more embodiments, the composition comprises a small amount (e.g., 1, 2, 3, 4, 5, 6, 7, 8, or 9 w/w %) of an organic carbonate ester, preferably, a dialkyl carbonate ester. Preferred are cyclic carbonate esters having a ring size from 4 to 7 atoms. One exemplary cyclic carbonate ester is propylene carbonate. See, e.g., formulations SS38-I, SS40-I, SS43-I and SS50-I (or IG).

The instant formulations may also contain small amounts, e.g., from 0.01 to 5 w/w %, more typically from 0.01 to 0.5 w/w % of an anti-oxidant. Exemplary anti-oxidants include, for example, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), ascorbic acid, tert-butyl hydroquinone, propyl gallate, and the like. In one or more particular embodiments, a topical composition as described herein contains butylated hydroxytoluene.

The compositions described may be in the form of solutions, suspensions, emulsions, ointments, lotions, gels, and the like. Emulsions of the form oil-in-water or water-in-oil are contemplated, particular for non-itraconazole containing formulations. The compositions are topically applied directly to the skin, for example, with the fingertips of a subject in need or by a caregiver, or for example, by spraying the solution or suspension onto the skin.

Gels are formed by the entrapment of large amounts of aqueous or aqueous-alcoholic liquids in a network of colloidal solid particles. These colloids are typically present at concentrations of less than 10% w/w and are also referred to as gelling agents or thickening agents, also mentioned herein above. Examples of suitable gelling agents include carboxymethyl cellulose, hydroxypropylmethyl cellulose, hydroxyethyl cellulose, methyl cellulose, sodium alginate, alginic acid, pectin, tragacanth, carrageen, agar, clays, aluminium silicate, carbomers, etc.

For formulations comprising itraconazole, the gelling agent hydroxypropyl cellulose (HPC) is preferred, in particular for use in formulations in which a smooth, non-particulate containing formulation is desired. Illustrative amounts of a gelling agent, as mentioned above, are typically less than 10 w/w %, and are often less than 5 w/w %. For instance, a formulation as provided herein may comprise 1, 2, 3, 4, or 5 w/w percent of a gel forming agent. In some embodiments, the formulation comprises from 1-3 w/w % of a gel forming agent. In one or more embodiments, the hedgehog inhibitor is itraconazole and the thickening agent is hydroxypropyl cellulose; in another embodiment, the hedgehog inhibitor is itraconazole and the thickening/gelling agent is hydroxypropylcellulose having a weight average molecular weight between about 50,000 to 150,000 Daltons, or from about 60,000 to about 125,000 Daltons, or preferably from about 80,000 to about 100,000 Daltons.

Creams and ointments may also be utilized. They are emulsions of oleaginous substances and water (i.e. the carrier). The cream may be a water-in-oil (w/o) in which an aqueous phase is dispersed in an oil phase, or an oil-in-water (o/w) which have an oil dispersed within an aqueous base. An ointment is also contemplated, and is typically more viscous than an o/w cream. Traditional ointment bases (i.e. the carrier) include hydrocarbons (petrolatum, beeswax, etc.) vegetable oils, fatty alcohols (cholesterol, lanolin, wool alcohol, stearyl alcohol, etc.) or silicones. Pastes are a type of ointment into which a high percentage of insoluble particulate solids have been added, up to 50% by weight. Insoluble solids such as starch, zinc oxide, calcium carbonate, or talc may be used.

Aerosols may also be utilized. The compound may be dissolved in a propellant and a co-solvent such ethanol, acetone, hexadecyl alcohol, etc. Foaming agents may be incorporated to produce a mousse.

In some embodiments directed to topical formulations in which the hedgehog inhibitor compound is itraconazole, the composition does not contain a surfactant. In some other embodiments directed to topical formulations comprising the hedgehog inhibitor, itraconazole, the composition is absent a triglyceride. In yet some further embodiments related to topical formulations in which the hedgehog inhibitor compound is itraconazole, the composition is absent a complexing agent such as a cyclodextrin. In yet one or more further embodiments of a topical formulation comprising the hedgehog inhibitor, itraconazole, the composition is not an oil-in-water emulsion and does not contain a hydrophobic oil. In certain further embodiments, the itraconazole-containing composition does not contain a surfactant, or a triglyceride, or a complexing agent, or a hydrophobic oil.

Formulations having the characteristics described herein, e.g., the particular composition components and relative amounts and ranges of each, were devised based at least in part upon hedgehog inhibitor solubility, as well as system compatibility, and stability of the hedgehog inhibitor in the formulation over time. Following an investigation of short-term stability, as described in detail in Example 8, itraconazole-containing formulations having particular advantageous features were further examined for their in-vitro skin permeation. These exemplary topical formulations are described in tabular form below. The “IG-2” designation of the samples refers to an itraconazole-containing gel formulation containing 2 w/w % of a gel forming agent.

TABLE 5-1 Exemplary Topical Compositions SS-37- SS-38 SS-40 SS-43 SS-50 IG2 IG2 IG2** IG2 IG2 wt % wt % wt % wt % wt % ethanol 56.80  47.65  47.65  22.20  — DEGEE 25.00  25.00  — 25.00  25.00  PEG-400 — — 25.00  — — N-methyl pyrrolidone — — — 25.00  — TERNARY — — — — 10.00/ COMBINATION 19.75/ Glycerol/propylene 17.90 glycol/PEG-400 dimethyl isosorbide 15.00  15.00  15.00  15.00  15.00  benzyl alcohol — 5.00 5.00 5.00 5.00 phenoxyethanol 1.00 — — — — propylene carbonate — 5.00 5.00 5.00 5.00 Butylated 0.10 0.10 0.10 0.10 0.10 hydroxytoluene hydroxypropyl cellulose 2.0  2.0  2.0  2.0  2.0  itraconazole 0.10 0.25 0.25 0.70 0.25 Ratio* monohydric 2.27 2.11 — 1.09 — alcohol/lower alkyl end capped oligomeric alkylene glycol *Includes ethanol and benzyl alcohol **Ratio of monohydric alcohol/non-end capped oligomeric alkylene glycol = 2.11

FIG. 4 shows the cumulative amount of itraconazole permeated across human skin in vitro, in ng/cm², as a function of time, in hours, for the five compositions of itraconazole in the exemplary solvent systems set forth in Table 5-1. The formulations identified as SS50-IG2 (* symbols) and SS43-IG2 (x symbols) each provided a cumulative amount of itraconazole of at least about 40 ng/cm² in 48 hours. The formulation, SS50-IG2, had the highest flux of the formulations tested and also achieved the highest cumulative amount of itraconazole delivered across the skin in 48 hours. Formulation SS43-IG2 exhibited the next highest flux and a similarly achieved the second highest cumulative amount of itraconazole delivered across the skin in 48 hours. Two of the formulations, SS37-IG2 (closed squares) and SS38-IG2 (closed triangles), achieved a cumulative amount of itraconazole of at least about 10 ng/cm² in 48 hours. The formulation identified as SS40-IG2 (closed diamonds) achieved a cumulative amount of itrazonazole of at least about 3 ng/cm² in 48 hours. Thus, the instant topical formulations are capable of permeating through human skin and also of achieving concentrations of itraconazole in the skin effective to achieve a cellular response.

To further assess the ability of the formulations to achieve intracutaneous delivery, the concentration of hedgehog inhibitor compound (itraconazole) in the stratum corneum, epidermis and dermis was measured after 48 hours topical exposure to the test formulations each comprising itraconazole. Results of the analysis of the layers of the skin for concentration of itraconazole are shown in FIG. 5. The amount of itraconazole delivered to the stratum corneum was highest for the formulation identified as SS43-IG2, which provided nearly 2000 ng (actual value 1973.01 ng) to the stratum corneum after 48 hours of topical application. The same formulation, SS43-IG2, also delivered the highest amount of itraconazole to both the epidermis (about 500 ng; actual value 503.54 ng) and the dermis (greater than 400 ng; actual value 427.93 ng) after 48 hours of topical application. The formulations identified as SS50-IG2 and SS38-IG2 also delivered beneficial levels of itraconazole to each of the stratum corneum, the epidermis and the dermis.

The formulation identified as SS50-IG2 delivered about 900 ng (actual value 898.47 ng) of itrazonazole to the stratum corneum, about 210 ng (actual value 209.29 ng) to the epidermis, and about 230 ng (actual value 228.81 ng) to the dermis after 48 hours of contact with the skin.

The formulation identified as SS38-IG2 delivered about 900 ng (actual value 883.33 ng) of itrazonazole to the stratum corneum, about 425 ng (actual value 426.71 ng) to the epidermis, and about 150 ng (146.91 ng) to the dermis after 48 hours of contact with the skin.

The topical formulations described herein are effective to provide an absolute concentration of hedgehog inhibitor compound such as patidegib or itraconazole in the living skin (epidermis and dermis) that is sufficient to have a molecular effect, i.e., suppress hedgehog signaling.

Accordingly, in one embodiment, a topical formulation of itraconazole is provided that achieves after 48 hours of topical application in vitro an amount of itraconazole in the epidermis, the dermis, or the epidermis and dermis combined that exceeds by at least about 150%, 200%, 300%, 350% or 400% the amount of itraconazole in the receiver fluid. In another embodiment, a topical formulation of itraconazole is provided that achieves after 48 hours of topical application in vitro an amount of itraconazole in the epidermis, the dermis, or the epidermis and dermis combined that is at least about 1.5, 2, 3, 3.5, 4 or 5 fold greater than the amount of itraconazole in the receiver fluid. As supported by the concentration values of itraconazole in each of the skin matrices for representative topical compositions of itraconazole in Table 9, the formulations described herein are effective to achieve therapeutically effective levels of itraconazole in the skin, since the concentrations of itraconazole achieved in each of the skin layers notably exceeds the 1050 value for itraconazole (0.8 μM, Kim and Beachy, Cancer Cell, 17, 388-399, 2010).

A wide variety of methods may be used for preparing the formulations described above. Broadly speaking, the formulations may be prepared by combining together the components of the formulations, as described herein, at a temperature and for a time sufficient to provide a pharmaceutically effective and elegant composition. The term “combining together”, as used herein, means that all of the components of the compositions may be combined and mixed together at about the same time. The term “combining together” also means that the various components may be combined in one or more sequences to provide the desired product. The formulation can be prepared on a weight/weight (w/w) or a weight/volume (w/v) basis depending upon the form of the final dosage form.

The compositions may be packaged for use in a medical setting or for retail distribution directly to the consumer (i.e., an article of manufacture or kit). Such articles will be labeled and packaged in a manner advising the patient how to use the product for therapy. Such instructions will include the duration of treatment, dosing schedule, precautions, etc. These instructions may be in the form of pictures, written instructions, or a combination thereof. They may be printed on the side of the packaging, be an insert, or any other form of communication appropriate for the retail market.

It will be appreciated that, in other embodiments, the compositions can be incorporated into a topical delivery system that is applied to the skin. Topical delivery systems are well described in the literature and can take the form of a reservoir type system with a backing member secured to a membrane to device a reservoir for the composition. An adhesive is included about the periphery of the membrane to secure the system to the skin. Other examples of delivery systems that may be used for topical application of the formulations described herein are summarized, for example, in R. W. Baker and J. Farrant “Patents in transdermal drug delivery”, Drug Delivery Systems 1987 Conference Proceedings, and the patents noted therein describing delivery devices are incorporated by reference herein.

C. Methods of Treating

The compositions described herein are, in one aspect, for treating a hedgehog-associated cancer or tumor. The tumor can be a solid tumor, a soft tissue tumor, or a metastatic lesion. In one embodiment, the compositions are for the treatment of skin cancer or more specifically of squamous cell carcinoma, keratoacanthoma, melanoma, or basal cell carcinoma. In one embodiment, the skin cancer is basal cell carcinoma. In yet a further embodiment, a method of treating a subject with Gorlin syndrome is provided, where the subject presents with or is at risk of presenting with basal cell carcinoma.

For treatment of a skin cancer, the composition is applied topically to the subject. In one embodiment, the topical application is to the region of the skin presenting with a cancerous lesion, and in other embodiments, the topical application is to a region of the skin that is not presenting with a cancerous lesion—e.g., the composition is applied topically to healthy skin for prevention. In one particular embodiment, the composition is applied directly to the cancerous lesion.

For illustrative itraconazole based formulations, e.g., containing from about 0.1 to about 2 w/w % itraconazole, a single dose full face application will typically correspond to about 0.1 mg to about 2 mg of itraconazole, assuming application of approximately 125 milligrams of gel to the face.

The composition is applied to the skin, in various embodiments, once a month, once every two weeks, once every 10 days, once a week, twice a week, three times a week, every other day, once daily, twice daily, three times daily or four times daily, etc. The dosing schedule will depend, as can be appreciated, by factors well known in medical arts, including the dose of drug compound in the composition, the particular hedgehog inhibitor compound, additional therapeutic agents, if present, the type of cancer or condition to be treated, and the health of the patient.

The methods and compositions can optionally be used in combination with one or more other cancer therapies (e.g., one or more therapeutic agents, surgery and/or radiation). In one or more embodiments, the methods and compositions are used in combination with a surgical procedure and/or radiation therapy. Surgical procedures include, but are not limited to, excision, curettage and electrosurgery, cryosurgery, Mohs micrographic surgery, and laser surgery. Excision is useful for both primary and recurrent tumors and has the advantage of allowing for histological assessment of surgical margins. Curettage and electrosurgery involves alternately removing soft tumor tissue with a curette and then destroying an extra margin of tissue by electrodesiccation, electrocautery, or electrocoagulation. Cryosurgery involves freezing the tumor to a temperature that kills the cells of the tumor. The dead tumor cells can be removed by, for example, curettage. Mohs micrographic surgery (MMS) involves a surgeon using a microscope to identify the margin of the tumor more accurately and more precisely than is possible by unaided visual inspection. MMS can increase the likelihood that the entire tumor is removed and minimize the amount of normal tissue that is removed. Laser surgery involves using a laser to vaporize tumor cells or use of a laser in lieu of a scalpel blade for excisional surgery.

In other embodiments, the methods and compositions provided herein are used in combination with one or more therapeutic agents. Any combination of the hedgehog inhibitor composition and other cancer therapies (e.g., one or more additional therapeutic agents, surgery and/or radiation) can be used. For example, a topical hedgehog inhibitor composition as described herein may comprise one or more additional therapeutic agents, or may be administered in conjunction with another type of therapy or treatment. Additionally, the hedgehog inhibitor composition and/or other cancer therapies can be administered or carried out during periods of active disorder, or during a period of remission or less active disease. The hedgehog inhibitor composition and other cancer therapies as applicable can be administered before treatment, concurrently with treatment, post-treatment, or during remission of the disorder or condition being treated. In one embodiment, the method or composition comprises a combination of patidegib and itraconazole.

In a further aspect, topically formulated itraconazole may be administered in conjunction with another topical drug such as but not limited to patidegib, to thereby prevent or inhibit degradation of the topical drug (e.g., patidegib), e.g., by cytochrome-based degradation mechanisms, in the skin. By reducing its metabolism in the living skin, one may be able to provide a lower dose of patidegib (or another topical agent) than could otherwise be achieved (e.g., in the absence of a combination with itraconazole) to achieve a therapeutically effective concentration of drug in the skin. In one or more further related embodiments, topical patidegib, e.g., comprised within a composition or delivery system as provided herein, is administered in conjunction with another topical azole drug such as fluconazole, or ketoconazole, to thereby prevent or lessen degradation of the patidegib, e.g., by cytochrome-based degradation mechanisms, in the skin. The topical administration of an azole drug such as itraconazole may therefore be effective to improve the efficacy of a topical or even systemically administered drug such as patidegib due to local inhibition of degradation mechanisms that function to metabolize the drug in the skin.

A study was conducted to evaluate the toxicokinetics of patidegib when administered twice daily via dermal application for 13 weeks. As described in Example 11, the formulation identified herein as SS14 was prepared, with patidegib concentrations of 2% and 4%. The formulations, along with a placebo, were applied topically to Gottingen Minipigs® twice daily, and blood samples were collected on study days 1, 14 and 90 for analysis of patidegib and its metabolite, IPI-230.

The mean concentration-time profiles of patidegib in plasma for the test groups (male and female results combined) are presented graphically in FIG. 6A and the mean concentration-time profiles of IPI-230 in plasma for the test groups (male and female results combined) are presented graphically in FIG. 6B. The dose normalized C_(max) and AUC₀₋₂₄ relationships of patidegib in Gottingen Minipig® plasma are presented graphically in for the combined sexes in FIGS. 7A-7B. After dermal administration, patidegib was absorbed. Individual T_(max) values were observed 2 to 8 hours post the first or second dose on Day 1, and 2 to 6 hours post the first or second dose on Days 14 and 90. The mean concentration-time profiles for the combined sexes (FIG. 6A) show that exposure to patidegib generally increased with the increase in dose level from 40 to 80 mg/kg/day on Day 90. The data also shows that after dermal administration of patidegib, IPI-230 appeared in plasma (FIG. 6B). Individual T_(max) were observed 2 to 8 hours post the first or second daily dose on Days 14 and 90. The exposure, as assessed by patidegib mean C_(max) and AUC₀₋₂₄ values, increased with the increase in patidegib dose level from 40 to 80 mg/kg/day on Day 90. The increases in patidegib mean C_(max) and AUC₀₋₂₄ values were generally dose proportional, as presented FIGS. 7A-7B.

Exposure to patidegib increased with the increase in dose level from 40 to 80 mg/kg/day on Day 90. The increases in patidegib mean C_(max) and AUC₀₋₂₄ values on Day 90 were generally greater than dose proportional. Patidegib mean C_(max) and AUC₀₋₂₄ values were generally greater than 4-fold higher in females, when compared to males, on Days 14 and 90. Patidegib Day 14 to Day 1 ratio values ranged from 45.8 to 139 and from 70.7 to 218 for mean C_(max) and AUC₀₋₂₄, respectively. Patidegib Day 90 to Day 1 ratio values ranged from 7.89 to 28.4 and from 9.18 to 39.9 for mean C_(max) and AUC₀₋₂₄, respectively. Additionally, mean C_(max) and AUC₀₋₂₄ were generally lower on Day 90 when compared to Day 14.

Exposure to the patidegib metabolite IPI-230 was demonstrated following twice daily administration of patidegib at 80 mg/kg/day on Days 14 and 90. IPI-230 mean C_(max) and AUC₀₋₂₄ values were greater than 2-fold in females when compared to males. Mean C_(max) and AUC₀₋₂₄ values could not be compared to Day 1, as Day 1 values for IPI-230 were generally below the limit of quantification (BLQ). The mean metabolite to parent ratios ranged from 0.00535 to 0.00738 and from 0.00524 to 0.00702, for C_(max) and AUC₀₋₂₄, respectively. In summary, the study in Example 11 demonstrated that exposure to patidegib increased with the increase in dose level from 40 to 80 mg/kg/day on Day 90. Exposure to IPI-230 was demonstrated following twice daily administration of Patidegib at 80 mg/kg/day on Days 14 and 90. The study also demonstrated that the increases in patidegib mean C_(max) and AUC₀₋₂₄ values on Day 90 were generally dose proportional. Patidegib and IPI-230 mean C_(max) and AUC₀₋₂₄ values were generally greater than 2-fold higher in females when compared to males. Patidegib Day 14 to Day 1 ratio values ranged from 45.8 to 139 and from 70.7 to 218 for mean C_(max) and AUC₀₋₂₄, respectively. Patidegib Day 90 to Day 1 ratio values ranged from 7.89 to 28.4 and from 9.18 to 39.9 for mean C_(max) and AUC₀₋₂₄, respectively. IPI-230 Day 14 and Day 90 mean C_(max) and AUC₀₋₂₄ values could not be compared to Day 1, as Day 1 values for IPI-230 were generally BLQ. The mean metabolite to parent ratios ranged from 0.00535 to 0.00738 and from 0.00524 to 0.00702, for C_(max) and AUC₀₋₂₄, respectively.

III. Examples

The following examples are illustrative in nature and are in no way intended to be limiting.

Example 1 Topical Formulations

The hedgehog inhibitor compound patidegib and the following solvent systems were prepared as topical formulations.

TABLE 1-1 Topical Formulation SS5 Ratio EtOH + Ratio Component w/w % BnOH/PG Ethanol/PG ethanol 18.73 1.1 1.0 propylene glycol 18.73 benzyl alcohol 1.87 diethylene glycol monoethyl 18.73 ether* buffer, pH 7.5 35.59 hydroxypropyl cellulose 2.00 (HPC; Klucel HF grade) patidegib 4.35 *abbreviated herein as “DEGEE” and also known as 2-(2-ethoxyethoxy)ethanol and sold under the tradename Transcutol ® P

TABLE 1-2 Topical Formulation SS6 Ratio EtOH + Ratio Component w/w % BnOH/PG Ethanol/PG ethanol 27.54 1.60 1.5 propylene glycol 18.36 benzyl alcohol 1.84 diethylene glycol monoethyl 18.36 ether buffer, pH 7.5 25.70 hydroxypropyl cellulose 2.00 patidegib 6.21

TABLE 1-3 Topical Formulation SS14 Ratio Component w/w % Ethanol/PG ethanol 23.49 1.25 propylene glycol 18.79 diethylene glycol monoethyl 18.79 ether buffer, pH 7.5 31.01 phenoxyethanol 0.94 hydroxypropyl cellulose 2.00 patidegib 4.97

TABLE 1-4 Topical Formulation SS20 Ratio EtOH + Ratio Component w/w % BnOH/PG Ethanol/PG ethanol 23.81 1.35 1.25 propylene glycol 19.05 benzyl alcohol 1.90 buffer, pH 7.5 49.52 hydroxypropyl cellulose 2.00 patidegib 3.73

TABLE 1-5 Topical Formulation SS22 Ratio EtOH + Ratio Component w/w % BnOH/PG Ethanol/PG ethanol 47.30 1.62 1.56 propylene glycol 30.27 benzyl alcohol 1.89 isostearic acid 14.19 hydroxypropyl cellulose 2.00 patidegib 4.35

The permeation of patidegib into human skin from the five formulations was tested in vitro using Franz diffusion cells. Franz diffusion cells with a surface area of about 0.6 cm² and a volume of 2.0 mL were used. Skin from an abdominoplasty was dermatomed to approximately 400 micrometers (μm). The receiver side of the cell was filled with ethanol/water 20/80 and the cells were maintained at 37±0.5° C. Each test formulation was dosed into the sample side of the cells using a 1 mL plunger and positive displacement pipette. The weight of the plunger was determined before and after dispensing formulation into each cell to dispense a 6-7 mg dose of formulation (approximately 10 mg/cm²). Each formulation was tested in six diffusion cells (n=6). A 200 μl aliquot of receiver fluid was removed from each cell at 0 hours, 14 hours, 18 hours, 24 hours, 36 hours, 40 hours, 44 hours and 48 hours. Following the 48 hour time point, the Franz cells were dismantled to recover the skin for analysis. The concentration of patidegib in the stratum corneum, epidermis and dermis was determined using tissue homogenization and solvent extraction (80/20 v/v ethanol/water) and analysis via LC MS/MS. Results are shown in FIGS. 1A-1B.

Example 2 Topical Formulations

The hedgehog inhibitor compound patidegib and the following solvent systems were prepared as topical formulations.

TABLE 2-1 Topical Formulation SS14.10 Ratio Component w/w % Ethanol/PG ethanol 7.37 1.50 propylene glycol 4.91 diethylene glycol monoethyl ether 9.83 (DEGEE) phenoxyethanol 0.98 deionized water 74.16 hydroxypropyl cellulose 2.00 patidegib 0.75

TABLE 2-2 Topical Formulation SS14.19 Component w/w % phenoxyethanol 0.99 deionized water 96.91 hydroxypropyl cellulose 2.00 patidegib 0.10

TABLE 2-3 Topical Formulation SS22.7 Ratio Component w/w % Ethanol/PG isopropyl alcohol 49.13 1.56 propylene glycol 31.44 isostearic acid 16.68 hydroxypropyl cellulose 2.00 patidegib 0.75

TABLE 2-4 Topical Formulation SS22.9 Ratio Component w/w % Ethanol/PG isopropyl alcohol 49.45 0 propylene glycol — isostearic acid 24.72 isopropyl myristate 23.74 hydroxypropyl cellulose 2.00 patidegib 0.10

The permeation of patidegib into human skin from the formulations identified in Example 1 as SS14 and SS22 and the formulations identified above as SS14.10, SS14.19, SS22.7 and SS22.9 were tested in vitro using Franz diffusion cells. Franz diffusion cells with a surface area of about 0.6 cm² and a volume of 2.0 mL were used. Skin from an abdominoplasty was dermatomed to approximately 400 micrometers (μm). The receiver side of the cell was filled with ethanol/water 20/80 and the cells were maintained at 37±0.5° C. Each test formulation was dosed into the sample side of the cells using a 1 mL plunger and positive displacement pipette. The weight of the plunger was determined before and after dispensing formulation into each cell to dispense a 6-7 mg dose of formulation (approximately 10 mg/cm²). Each formulation was tested in six diffusion cells (n=6). A 200 μL aliquot of receiver fluid was removed from each cell at 0 hours, 14 hours, 18 hours, 24 hours, 36 hours, 40 hours, 44 hours and 48 hours. Following the 48 hour time point, the Franz cells were dismantled to recover the skin for analysis. The concentration of patidegib in the stratum corneum, epidermis and dermis was determined using tissue homogenization and solvent extraction (80/20 v/v ethanol/water). Results are shown in FIGS. 2A-2B.

Example 3 Topical Formulations with Patidegib

The hedgehog inhibitor compound patidegib and the following solvent systems were prepared as topical formulations.

TABLE 3-1 Topical Compositions Aqueous Formulations Non-aqueous Formulations SS14 SS14D1 SS14D2 SS22 SS22D1 SS22D2 wt % wt % wt % wt % wt % wt % ethanol 23.5 23.5 23.5 47.3 47.3 47.3 propylene glycol 18.8 18.8 18.8 30.3 30.3 30.3 benzyl alcohol — — — 1.9 1.9 1.9 DEGEE* 18.8 18.8 18.8 isostearic acid — — — 14.2 18.4 17.8 phenoxyethanol 0.9 0.9 0.9 — — — buffer 31.0 35.9 35.2 — — — hydroxypropyl cellulose 2.0 2.0 2.0 2.0 2.0 2.0 patidegib 5.0 0.1 0.75 4.4 0.1 0.75 Ratio monohydric alcohol/diol 1.25 1.25 1.25 1.62 1.62 1.62 *DEGEE = diethylene glycol monoethyl ether (Transcutol ® P)

The permeation of patidegib into human skin from the formulations was tested in vitro using Franz diffusion cells. Franz diffusion cells with a surface area of about 0.6 cm² and a volume of 2.0 mL were used. Skin from an abdominoplasty was dermatomed to approximately 400 micrometers (μm). The receiver side of the cell was filled with ethanol/water 20/80 and the cells were maintained at 37±0.5° C. Each test formulation was dosed into the sample side of the cells using a 1 mL plunger and positive displacement pipette. The weight of the plunger was determined before and after dispensing formulation into each cell to dispense a 6-7 mg dose of formulation (approximately 10 mg/cm²). Each formulation was tested in six diffusion cells (n=6). A 200 μL aliquot of receiver fluid was removed from each cell at 0 hours, 14 hours, 18 hours, 24 hours, 36 hours, 40 hours, 44 hours and 48 hours. Following the 48 hour time point, the Franz cells were dismantled to recover the skin for analysis. The concentration of patidegib in the stratum corneum, epidermis and dermis was determined using tissue homogenization and solvent extraction (80/20 v/v ethanol/water). Results are shown in FIGS. 3A-3B.

Example 4 Stability of Exemplary Patidegib Topical Formulations

Stability of the exemplary formulations (SS5, SS6, SS14, SS20 and SS22) was assessed by analyzing the formulations for patidegib content after four weeks storage at 25° C. and at 40° C. Results are shown in the tables below.

TABLE 4-1 Stability of Exemplary Formulations - Mean Percentage Recovery of Patidegib Mean percentage recovery of patidegib from theoretical (n = 3, lowest-highest value) Formu- patidegib t = 2 weeks t = 4 weeks lation (% w/w) t = 0 25° C. 40° C. 25° C. 40° C. SS5 4.35 97.88 109.82 106.51 97.61 96.24 (Aq.) (95.44- (105.24- (106.25- (97.40- (95.59- 100.31) 113.56) 106.64) 97.88) 97.06) SS6 6.21 98.75 110.90 111.99 100.60 97.75 (Aq.) (97.24- (109.77- (109.75- (99.11- (97.28- 100.28) 111.51) 114.30) 102.79) 98.30) SS14 4.97 102.44 131.46 105.62 99.07 96.63 (Aq.) (101.61- (127.08- (105.19- (98.39- (95.93- 103.61) 134.03) 106.25) 99.51) 97.85) SS20 3.73 107.89 65.38 104.49 102.05 97.71 (Aq.) (107.11- (63.42- (103.57- (100.38- (97.10- 108.30) 67.35) 105.46) 103.72) 98.24) SS22 4.35 114.96 100.24 93.98 100.25 99.57 (Non- (114.48- (99.66- (88.29- (100.18- (98.89- Aq.) 115.40) 101.34) 103.31) 100.29) 99.93)

TABLE 4-2 Stability of Exemplary Formulations - Peak Purity of Patidegib Mean percentage area/area of patidegib (n = 3, lowest-highest value) Formu- patidegib t = 2 weeks t = 4 weeks lation (% w/w) t = 0 25° C. 40° C. 25° C. 40° C. SS5 4.35 99.49 99.63 99.52 99.28 99.30 (Aq.) (98.78- (99.60- (99.47- (99.26- (99.23- 99.87) 99.66) 99.60) 99.30) 99.38) SS6 6.21 100.00 99.71 99.41 99.08 99.25 (Aq.) (100.00- (99.68- (99.31- (99.00- (99.20- 100.00) 99.77) 99.48) 99.15) 99.28) SS14 4.97 100.00 99.67 99.49 99.33 99.28 (Aq.) (100.00- (99.65- (99.35- (99.32- (99.26- 100.00) 99.69) 99.67) 99.33) 99.31) SS20 3.73 99.89 99.67 99.46 99.31 99.27 (Aq.) (99.88- (99.67- (99.33- (99.28- (99.23- 99.90) 99.67) 99.61) 99.34) 99.31) SS22 4.35 100.00 99.94 99.95 99.92 99.84 (Non- (100.00- (99.92- (99.92- (99.91- (99.83- Aq.) 100.00) 99.95) 99.98) 99.93) 99.87)

TABLE 4-3 Stability of Exemplary Formulations SS14 and SS22 - Peak Purity of Patidegib Storage condition Percentage patidegib peak purity (%) Formulation (° C.) T = 0 T = 4 week T = 8 week SS14 25 99.72 99.82 99.89 40 99.88 99.87 SS22 25 99.65 99.88 99.10 40 99.82 99.54

TABLE 4-4 Stability of Exemplary Formulations SS14 and SS22 - Mean Percentage Recovery of Patidegib Storage condition T = 2 T = 4 T = 8 Formulation (° C.) T = 0* week week week SS14 25 100.61 109.04 103.44 102.45 (99.81- (106.62- (102.99- (102.38- 101.30) 111.51) 103.85) 102.56) 40 103.42 103.10 103.17 (102.23- (102.91- (102.13- 104.59) 103.20) 104.40) SS22 25 95.78 98.51 99.90 97.74 (94.02- (98.13- (99.48- (97.46- 99.09) 99.19) 100.19) 98.03) 40 104.24 98.64 98.92 (102.30- (98.17- (98.51- 106.85) 98.89) 99.28)

The patidegib content for all formulations at t=0 was between 97-117% of the theoretical concentration. The peak purity of the patidegib formulation at t=0 was greater than 99%. After 2 weeks of storage at 25° C. and at 40° C., the peak purity of all formulations were comparable to the starting peak purity at t=0 and observed to be greater than 99%. The patidegib content for the formulations 2 weeks of storage at 25° C. and at 40° C. was between 65-131% of the theoretical concentration. After 4 weeks of storage at 25° C. and at 40° C. the patidegib content of all formulations was between 95-105% of the theoretical concentration. The peak purity of all formulations was greater than 99% and comparable to the peak purity at t=0, with the exception of SS5 at 40° C. which was 98.58% and slightly lower than the t=0 value of 99.85%. Thus, the formulations are stable at room temperature (20-25° C.) and up to 40° C. for at least about 4 weeks.

Example 5 Skin Irritation of Exemplary Patidegib Topical Formulations

Skin irritation of three exemplary formulations prepared as described in Example 1 was assessed in Gottingen minipigs. The test formulations were:

1. “SS22, 3.5 wt % patidegib”, and comprising ethanol, benzyl alcohol, isostearic acid and propylene glycol, and HPC as a gelling agent;

2. “SS14, low PG, 4.0 wt % patidegib”, and comprising Transcutol P, ethanol, propylene glycol, buffer (pH 7.5; boric acid and sodium hydroxide) and phenoxyethanol and HPC as a gelling agent;

3. “SS14, 4.0 wt % patidegib”, and comprising Transcutol P, ethanol, propylene glycol, buffer (pH 7.5; boric acid and sodium hydroxide) and phenoxyethanol and HPC as a gelling agent;

4. SS22 placebo—same as formulation 1. above with no patidegib;

5. SS14, low PG placebo—same as formulation 2. above with no patidegib;

6. SS14 placebo—same as formulation 3. above with no patidegib;

In three minipigs, six application sites were identified; 3 sites on each side of the midline of the dorsal region of each animal. Each application measured 2×2 inches and the sites were marked at the corners with an indelible marker. Prior to administration, the hair was clipped from the back of each animal. Each test article and placebo (1 mL/site) was distributed over the prescribed area by gentle inunction with a stainless steel spatula for 14 consecutive days. The test article was applied evenly with a thin, uniform film and the area was not occluded. For the initial dose, the material was applied in 0.25-0.5 mL/kg increments until the maximum feasible volume was identified to be 1 mL/kg application. Beginning on Day 2, the dosing sites were gently wiped with a wiping cloth (WYPALL®) wet with tap water to remove any residual material.

Daily observations of the test sites on each pig were made. For the SS22 formulation, very slight erythema was noted in ⅔ pigs beginning on Day 2. This progressed to well-defined to moderate-to-server incidences of the course of the 14 days. By Day 14, very slight to moderate-to-severe erythema was present in all animals. Because the same observations were made for the test and placebo SS22 test articles (numbers 1 and 4 above), the erythema may be vehicle related rather than drug related. For the SS14 formulations (numbers 2, 3, 5 and 6 above), no erythema or edema was noted at any time point on either the active or placebo test sites.

Example 6 Combination Solvent Systems for Topical Administration of a Hedgehog Inhibitor

The hedgehog inhibitor compound itraconazole and the following solvent systems were prepared as topical formulations. The solvent systems were devised following solubility experiments in which the saturated solubility of itraconazole in various solvents after a minimum of 24 hours stirring at 25° C. was investigated. Itraconazole is highly insoluble in water. However, following initial solubility experiments, itraconazole was found to exhibit a solubility between 0.01-0.05% w/w in dimethicone 350 CST, diisopropyl adipate, ethanol and castor oil; in dimethyl isosorbide, itraconazole exhibits a solubility of 2.32% w/w. A higher solubility was observed in benzyl alcohol and phenoxyethanol, of 14.97% and 7.87% w/w, respectively. Itraconazole demonstrated a saturated solubility in N-methyl pyrrolidone of 7.65% w/w. For the remaining solvents in which itraconazole solubility was investigated (not shown), the drug possessed a solubility between 0.01-0.20% w/w. Following several screening studies in which various mixed solvent systems were explored to assess solubility, system compatibility, and storage stability of itraconazole, the following optimized non-aqueous formulations were prepared.

TABLE 5-A Theoretical composition (%, w/w) Excipient SS36-I SS37-I SS38-I SS40-I SS42-I SS43-I Phenoxyethanol — 1 — — — — Benzyl alcohol 5 — 5 5 5 5 diethylene glycol 25 25 25 — 25 25 monoethyl ether Ethanol 53.9 57.9 48.9 48.9 28.9 23.9 PEG 400 — — — 25 — — N-methyl — — — — 25 25 pyrrolidone* dimethylisosorbide 15 15 15 15 15 15 Propylene — — 5 5 — 5 Carbonate Butylated 0.1 0.1 0.1 0.1 0.1 0.1 hydroxytoluene (BHT) Mean itraconazole 0.34 0.16 0.34 0.33 0.76 0.86 saturated solubility (0.23- (0.12- (0.30- (0.30- (0.72- (0.85- (%, w/w, lowest- 0.42) 0.19) 0.39) 0.37) 0.78) 0.88) highest value of n = 3) Mean itraconazole 100.00 100.00 100.00 100.00 100.00 100.00 % area/area (lowest- (100.00- (100.00- (100.00- (100.00- (100.00- (100.00- highest value of 100.00) 100.00) 100.00) 100.00) 100.00) 100.00) n = 3) Apparent pH of 7.14 7.03 6.79 8.24 7.44 7.61 solvent system with itraconazole *N-methyl-2-pyrrolidone, also known as N-methyl pyrrolidone, is sold under the trade name Pharmasolve ™.

TABLE 5-B Theoretical composition (%, w/w) Excipient SS44-I SS45-I SS46-I SS47-I SS48-I SS49-I SS50-I Phenoxyethanol — — 1 — — — — Benzyl alcohol 5 5 — 5 5 5 5 diethylene glycol 25 25 25 25 25 25 25 monoethyl ether Ethanol 53.9 53.9 32.9 23.9 23.9 — — Glycerol — — — — 10 10 10 Propylene glycol — — — — 20 20 20 PEG 400 — 15 — 15 — 23.9 18.9 N-methyl-2- — — 25 25 — — — pyrrolidone Dimethyl isosorbide 15 — 15 — 15 15 15 Propylene Carbonate — — — 5 — — 5 Butylated — 0.1 0.1 0.1 0.1 0.1 0.1 hydroxytoluene Butylated 0.1 — — — — — — hydroxyanisol (BHA) Mean itraconazole 0.25 0.14 0.67 0.59 0.23 0.27 0.32 saturated solubility (0.22- (0.13- (0.64- (0.58- (0.22- (0.26- (0.31- (%, w/w, lowest- 0.27) 0.15) 0.69) 0.59) 0.24) 0.29) 0.33) highest value of n = 3) Mean itraconazole 100.00 100.00 100.00 100.00 100.00 100.00 100.00 % area/area (lowest- (100.00- (100.00- (100.00- (100.00- (100.00- (100.00- (100.00- highest value of 100.00) 100.00) 100.00) 100.00) 100.00) 100.00) 100.00) n = 3) Apparent pH of 7.04 8.88 7.33 9.26 6.8 7.7 7.61 solvent system with itraconazole

The solubility of itraconazole in all of the additional solvent systems generated (SS36-I to SS50-I) was between about 0.24-0.86% w/w of itraconazole, with the exception of SS37 and SS45 where the solubility was approximately 0.15 w/w of itraconazole. Topical formulations of itraconazole will generally contain from about 0.10 w/w % itraconazole to about 10 w/w % itraconazole, or more typically will contain from about 0.10 w/w % itraconazole to about 5 w/w % itraconacole, or more typically from about 0.1-2 weight percent itraconazole.

Example 7 Non-Aqueous Gels for Topical Administration of a Hedgehog Inhibitor

Following the exploration and identification of the mixed solvent systems identified in Tables 5A and 5B, and following acceptable four week compatibility results, non-aqueous gels based on the formulations described in Example 6 were prepared. The gel formulations were slightly viscous to highly viscous gels, with viscosity increasing with the amount of HPC in the solvent system (e.g., from 1% to 2% w/w). Based upon initial formulation experiments, the gelling agents Carbopol 980 and hydroxypropyl methylcellulose appeared to be incompatible with itraconazole and the solvent systems employed, with a white precipitate forming during formulation.

TABLE 6-A Representative Non-aqueous gels for Topical Administration Theoretical composition (%, w/w) SS36- SS37- SS38- SS40 SS42- SS43- IG 1% IG 1% IG 1% 1% IG 1% IG 1% Excipient HPC P HPC P HPC P HPC P HPC P HPC P Phenoxyethanol — 1 — — — — Benzyl alcohol 5 — 5 5 5 5 diethylene glycol 25 25 25 — 25 25 monoethyl ether Ethanol 53.9 57.9 48.9 48.9 28.9 23.9 PEG 400 — — — 25 — — N-methyl-2-pyrrolidone — — — — 25 25 Dimethyl isosorbide 15 15 15 15 15 15 Propylene Carbonate — — 5 5 — 5 Butylated 0.1 0.1 0.1 0.1 0.1 0.1 hydroxytoluene (BHT) Hydroxypropylcellulose 1 1 1 1 1 1 Apparent pH 7.03 7.06 7.24 8.31 7.74 7.84

TABLE 6-B Representative Non-Aqueous Gels for Topical Administration Theoretical composition (%, w/w) SS44- SS45- SS46- SS47- SS48- SS49- SS50- IG 1% IG 1% IG 1% IG 1% IG 1% IG 1% IG 1% Excipient HPC P HPC P HPC P HPC P HPC P HPC P HPC P Phenoxyethanol — — 1 — — — — Benzyl alcohol 5 5 — 5 5 5 5 diethylene glycol 25 25 25 25 25 25 25 monoethyl ether Ethanol 53.9 53.9 32.9 23.9 23.9 — — Glycerol — — — — 10 10 10 Propylene glycol — — — — 20 20 20 PEG 400 — 15 — 15 — 23.9 18.9 N-methyl-2- — — 25 25 — — — pyrrolidone Dimethyl 15 — 15 — 15 15 15 isosorbide Propylene — — — 5 — — 5 Carbonate Butylated — 0.1 0.1 0.1 0.1 0.1 0.1 hydroxytoluene Butylated 0.1 — — — — — — hydroxyanisole Hydroxypropyl- 1 1 1 1 1 1 1 cellulose Apparent pH 7.07 8.93 7.89 9.28 6.68 7.70 7.61

A representative active gel comprising itraconazole with 1.5% HPC and 0.15% itraconazole was successfully formulated, forming a medium viscosity gel with no appearance of itraconazole crystals when observed under a microscope. Placebo gels were prepared for solvent systems SS36-IG to SS50-IG and containing HPC at 1% w/w. In all cases, the gels prepared were slightly hazy with a low to medium viscosity which flowed when tilted, with the exception of SS49 and SS50 which possessed a medium viscosity.

Example 8 Short-Term Stability of Non-Aqueous Gels for Topical Administration of a Hedgehog Inhibitor

A total of 16 formulations (including the corresponding placebos) were prepared for short-term stability testing. The representative formulations contain 2% w/w HPC (in contrast to the formulations above which contain 1% w/w HPC), and comprise from 0.1% w/w to about 1.0% w/w itraconazole. Only 14 of the 16 formulations prepared were placed on stability at 25 and 40° C. (and an additional temperature of 2-8° C.) in borosilicate glass vials, with the compositions of active formulations outlined in the tables below. The following tests were performed at each time point: 0, 2 and 4 weeks, for the assessment of the formulations placed on stability: visual appearance (macroscopic and microscopic appearance), apparent pH, and itraconazole content and peak purity.

Macroscopic Appearance

The formulations were visually assessed. At t=0, all active and placebo itraconazole gels were observed to be uniform, colourless with a high viscosity. Following 2 and 4 weeks storage at 25 and 40° C. all formulations were observed to be unchanged from t=0.

Microscopic Appearance

All formulations were assessed under the light microscope at 200 and 400× magnification and compared to their respective placebo formulations. Crystallisation was not observed in any of the active formulations at t=0 or following 2 and 4 weeks storage at 25 and 40° C.

Apparent pH

At t=0 the apparent pH of the itraconazole formulations was measured. The active itraconazole formulations possessed apparent pH values between 7.49 and 9.59 at t=0. Since all of the formulations placed on stability were non-aqueous based, the pH values are only “apparent pH” values, where the pH meter was standardized by use of an aqueous buffer solution. For the pH of the non-aqueous solutions, the ionization constant of the acid or base, the dielectric constant of the medium, the liquid junction potential (which may give rise to errors of 1 pH unit) and the hydrogen ion response of the glass electrode are all charged, giving rise to the “apparent pH”, which for the current purpose is to monitor any pH changes during the stability program. After 2 weeks stored at 25 and 40° C., the apparent pH values of active and placebo formulations were relatively comparable to t=0 where the apparent pH values showed a small decrease in pH (up to 0.5 pH units). After 4 weeks storage at 25 and 40° C. the apparent pH remained relatively comparable to t=2 weeks and t=0, with the final pH reading of each formulation falling within 0.5 pH units of t=0, with the exception of SS43-IG which was within 0.7 pH units of the initial pH reading.

Itraconazole Content and Peak Purity

The formulations were analysed for itraconazole content. Itraconazole content for all of the active formulations prepared for short term stability was 95-102% of the theoretical concentration. Peak purity of the itraconazole formulations at t=0 were all >99.39%. After 2 weeks storage at 25 and 40° C., the recovery and peak purity of all formulations were comparable to t=0, with the exception of SS33 at both temperatures and SS46-SS50 at 40° C. where a slight decrease in itraconazole recovery (approx. 92-96%) was observed. After 4 weeks storage at 25 and 40° C., the recovery of all formulations was observed to be between 95-100% of the theoretical concentration and comparable to t=0, with the exception of SS33 which showed a minimal decrease of between 4-5% from 102% to 98 and 97% at 25 and 40° C., respectively. The peak purity of all itraconazole formulations after 4 weeks storage at 25 and 4° C. were >99.4%, and comparable to the peak purity at t=0.

TABLE 7A Active formulations placed on stability Theoretical composition (%, w/w) SS36-IG2 SS37-IG2 SS38-IG2 SS40-IG2 SS42-IG2 SS43-IG2 SS33-IG2 2% HPC 2% HPC 2% HPC 2% HPC 2% HPC 2% HPC 2% HPC 0.18% 0.10% 0.25% 0.25% 0.55% 0.70% 0.25% Excipient Itr A Itr A Itr A Itr A Itr A Itr A Itr A Phenoxyethanol — 1.00 — — — — — Benzyl alcohol 5.00 — 5.00 5.00 5.00 5.00 5.00 diethylene 25.00 25.00 25.00 — 25.00 25.00 25.00 glycol monoethyl ether Ethanol 52.72 56.80 47.65 47.65 27.35 22.20 30.65 Propylene — — — — — — 20.00 glycol Solutol — — — — — — 2.00 PEG 400 — — — 25.00 — — — N-methyl-2- — — — — 25.00 25.00 — pyrrolidone Dimethyl 15.00 15.00 15.00 15.00 15.00 15.00 15.00 isosorbide Propylene — — 5.00 5.00 — 5.00 — carbonate Butylated 0.10 0.10 0.10 0.10 0.10 0.10 0.10 hydroxytoluene Hydroxypropyl- 2.00 2.00 2.00 2.00 2.00 2.00 2.00 cellulose Itraconazole 0.18 0.1 0.25 0.25 0.55 0.7 0.25 (API) Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00

TABLE 7B Active Formulations Placed on Stability Theoretical composition (%, w/w) SS44-IG2 SS45-IG2 SS46-IG2 SS47-IG2 SS48-IG2 SS49-IG2 SS50-IG2 2% HPC 2% HPC 2% HPC 2% HPC 2% HPC 2% HPC 2% HPC 0.18% 0.10% 0.50% 0.50% 0.18% 0.20% 0.25% Excipient Itr A Itr A Itr A Itr A Itr A Itr A Itr A Phenoxyethanol — — 1.00 — — — — Benzyl alcohol 5.00 5.00 — 5.00 5.00 5.00 5.00 diethylene 25.00 25.00 25.00 25.00 25.00 25.00 25.00 glycol monoethyl ether Ethanol 52.72 52.80 31.40 22.40 22.72 — — Propylene — — — — 20.00 19.80 19.75 glycol Glycerol — — — — 10.00 10.00 10.00 PEG 400 — 15.00 — 15.00 — 22.90 17.90 N-methyl-2- — — 25.00 25.00 — — — pyrrolidone Dimethyl 15.00 — 15.00 — 15.00 15.00 15.00 isosorbide Propylene — — — 5.00 — — 5.00 carbonate Butylated — 0.10 0.10 0.10 0.10 0.10 0.10 hydroxytoluene Hydroxypropyl- 2.00 2.00 2.00 2.00 2.00 2.00 2.00 cellulose Itraconazole 0.18 0.1 0.5 0.5 0.18 0.2 0.25 (API) Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00

Formulations selected for additional permeation/penetration experiments include SS37-102, SS38-IG2, SS-40-IG2, SS-43-IG2 and SS-50-IG2, based on solubility of itraconazole, solvent compatibility, apparent pH, and drug stability.

Example 9 Permeation/Penetration of Topical Formulations of Itraconazole

A permeation/skin penetration study was conducted based on formulations SS37-IG2, SS38-IG2, SS-40-IG2, SS-43-IG2 and SS-50-IG2, with sampling time points t=0, 14, 18, 24, 26, 36, 40, 44, and 48 hours following the same protocol as described in Example 1.

Components of each representative topical formulation are described below.

TABLE 8-01 Topical Formulation SS37-IG2 Component w/w % ethanol 56.80 w/w ratio EtOH + diethylene glycol monoethyl 25.00 phenoxyethanol/DEGMEE ether 2.3 Dimethyl isosorbide 15.00 w/w ratio DEGMEE/DMI 1.7 phenoxyethanol 1.00 hydroxypropyl cellulose 2.00 Butylated hydroxytoluene 0.10 itraconazole 0.10

TABLE 8-02 Topical Formulation SS38-IG2 Component w/w % ethanol 47.65 w/w ratio EtOH + diethylene glycol monoethyl 25.00 benzyl alcohol/DEGMEE ether 2.11 Dimethyl isosorbide 15.00 w/w ratio DEGMEE/DMI 1.7 Benzyl alcohol 5.00 Propylene carbonate 5.00 hydroxypropyl cellulose 2.00 Butylated hydroxytoluene 0.10 itraconazole 0.25

TABLE 8-03 Topical Formulation SS40-IG2 Component w/w % ethanol 47.65 w/w ratio EtOH + PEG-400 25.00 benzyl alcohol/PEG-400 2.11 Dimethyl isosorbide 15.00 w/w ratio PEG/DMI 1.7 Benzyl alcohol 5.00 Propylene carbonate 5.00 hydroxypropyl cellulose 2.00 Butylated hydroxytoluene 0.10 itraconazole 0.25

TABLE 8-04 Topical Formulation SS43-IG2 Component w/w % diethylene glycol monoethyl ether 25.00 N-methyl pyrrolidone 25.00 ethanol 22.20 w/w ratio EtOH + benzyl alcohol/DEGMEE 1.1 Dimethyl isosorbide 15.00 w/w ratio DEGMEE/DMI 1.7 Benzyl alcohol 5.00 Propylene carbonate 5.00 hydroxypropyl cellulose 2.00 Butylated hydroxytoluene 0.10 itraconazole 0.70

TABLE 8-05 Topical Formulation SS50-IG2 Component w/w % diethylene glycol monoethyl 25.00 w/w ratio ternary solvent system ether PPG, PEG, glycerol + Propylene glycol 19.75 benzyl alcohol/DEGMEE 2.12 PEG-400 17.90 Dimethyl isosorbide 15.00 w/w ratio DEGMEE/DMI 1.7 Glycerol 10.00 Propylene carbonate 5.00 Benzyl alcohol 5.00 hydroxypropyl cellulose 2.00 Butylated hydroxytoluene 0.10 itraconazole 0.25

FIG. 4 and FIG. 5 illustrate the results obtained from the full scale permeation and penetration experiments of itraconazole, respectively. The data generated in the penetration experiment was utilized to determine the concentration achieved in the Stratum corneum, epidermis and dermis summarized in Table 9. Given that the half maximal inhibitory concentration (IC50) for itraconazole is 0.8 μM, the tissue concentration of itraconazole is adequate to achieve a cellular response.

TABLE 9 Summary of concentration of itraconazole in each of the skin matrices (Stratum corneum, epidermis, dermis) (μM) after the final time point (48 h). Concentration of Concentration of Concentration of itraconazole (μM) itraconazole (μM) itraconazole (μM) Formulation in Stratum corneum. in epidermis. in dermis SS37-IG2 1819.6436 39.0019 10.3957 (Test Item 1) SS38-IG2 2086.3566 100.7848 11.9649 (Test Item 2) SS40-IG2 1151.2386 14.8867 6.7681 (Test Item 3) SS43-IG2 4660.0911 118.9332 34.8528 (Test Item 4) SS50-IG2 2122.1240 49.4327 18.6353 (Test Item 5)

FIG. 4 provides the cumulative amount of itraconazole permeated through human skin over a 48 hour time period for each of the test items. Formulations demonstrating the highest cumulative amount of itraconazole permeation were formulations SS50-IG2 and SS-43-IG2; these formulations exhibited the highest cumulative amount of itraconazole permeation at each of the time points evaluated, with SS-50 IG2 demonstrating the greatest overall skin permeation of itraconazole at each of the time points evaluated.

FIG. 5 provides information regarding recovery of itraconazole from each of the skin matrices (stratum corneum, epidermis, dermis) and receiver fluid, in nanograms, following the final 48 hour time point. SS-43-IG2 exhibited superior penetration into the stratum corneum, with notable levels of drug in both the epidermis and dermis as well.

Based upon a consideration of numerous factors including solubility of itraconazole, solvent system compatibility, apparent pH, formulation stability, and in-vitro skin permeation, representative preferred formulations include SS43-IG2, SS50-IG2 and SS38-IG2.

Example 10 Preparation of an Illustrative Itraconazole Topical Gel Formulation

A non-aqueous topical formulation of itraconazole was prepared as follows. Dehydrated ethanol was added to the formulation vessel, followed by addition of butylated hydroxytoluene (BHT) to the formulation vessel until dissolution. To the mixture was added diethylene glycol monoethyl ether (Transcutol® P), followed by N-methyl-2-pyrrolidone (Pharmasolve™). Dimethyl isosorbide was then added, followed by addition of propylene carbonate, and benzyl alcohol. The mixture was stirred by propeller until uniform. To the uniform mixture was added itraconazole until dissolved. Hydroxypropylcellulose was then added accompanied by propeller stirring. Once the HPC addition was complete, the resulting mixture was stirred until the HPC was fully dispersed. The exemplary formulation contains 0.7% w/w itraconazole.

A total single dose full face application of approximately 125 mg of gel corresponds to approximately 0.7 mg of itraconazole.

TABLE 10 Quantity per Formula 30 g Tube Material Supplier Grade (% w/w) Fill (g) Itraconazole Letco Medical USP 0.7 0.21 Decatur, AL Dehydrated alcohol Spectrum USP 22.2 6.66 New Brunswick, NJ Butylated Spectrum NF 0.1 0.03 hydroxytoluene New Brunswick, NJ Diethylene glycol Gattefosse NF 25.0 7.50 monoethyl ether Paramus, NJ (Transcutol P) N-methyl-2- Ashland JP 25.0 7.50 pyrrolidone Wilmington, (Pharmasolve) DE Dimethyl isosorbide Croda ≥98.0% 15.0 4.50 (Arlasolve Edison, NJ DMI-LQ) Propylene carbonate Penta NF 5.0 1.50 Fairfield, NJ Benzyl alcohol Spectrum NF 5.0 1.50 New Brunswick, NJ Hydroxylpropyl- Ashland NF 2.0 0.60 cellulose, Wilmington, (Klucel HF Pharm) DE

Example 11 In Vivo Administration of Patidegib Via Topical Delivery

A study was conducted to determine the toxicokinetics of patidegib and its metabolite, IPI-230, when patidegib was administered twice daily (approximately 8 hours apart) to Gottingen Minipigs® via dermal application for 13 weeks.

The formulation identified herein as SS14 was prepared, with 2% patidegib and with 4% patidegib. A placebo formulation was also prepared that was identical in all respects to SS14 except for the absence of the patidegib. The formulation was applied topically to the animals at patidegib dose levels of 0 mg/kg/day (untreated), 0 mg/kg/day (placebo), 40 mg/kg/day, and 80 mg/kg/day to Groups 1, 2, 3, and 4, respectively. Groups 1 and 3 consisted of four animals/sex/group and Groups 2 and 4 consisted of six animals/sex/group. Doses were administered twice daily (approximately 8 hours apart). Blood samples were collected from all animals, survival permitting, on Days 1, 14 (Group 4 only), and 90 predose and at approximately 2, 4, 6, 8 (just prior to the second daily dose), 10, 12, 14, 16, and 24 hours following the first daily dose. Plasma samples were assayed for patidegib and IPI-230. Only the 2-hour samples from the untreated and placebo groups were analyzed.

No. of Animals Approximate Dose Patidegib Group Male Female (mg/kg/day)^(a) 1 (Untreated) 4 4 0 2 (Placebo) 6 6 0 3 (2% Patidegib) 4 4 40 4 (4% Patidegib) 6 6 80 ^(a)Dose levels calculated assuming a test article density of 1 g/mL at an application rate of 2 mL/kg/day (1 mL/kg/dose) and based on an average body weight of 14 kg.

Noncompartmental analysis was applied to the individual plasma patidegib and IPI-230 concentration data for males and females. The following parameters were estimated: C_(max)—Maximum observed concentration; T_(max)—Time of maximum observed concentration; AUC_(Tlast)—Area under the concentration-time curve from hour 0 to the last measurable concentration, estimated by the linear trapezoidal rule; AUC₀₋₂₄—Area under the concentration-time curve from hour 0 to hour 24, estimated by the linear trapezoidal rule; DN AUC₀₋₂₄—Dose normalized AUC₀₋₂₄, calculated as AUC₀₋₂₄/dose level; DN C_(max)—Dose normalized C_(max), calculated as C_(max)/dose level. Some of the data is summarized in the tables below.

TABLE 11-1 Summary of the Mean Patidegib C_(max) and AUC₀₋₂₄ in Gottingen Minipig ® Plasma Dose Level C_(max) AUC₀₋₂₄ Interval Dose Group (mg/kg/day) Sex (ng/mL) (ng · hr/mL) Day 1 3 40 F 4.65 56.7 4 80 M 3.84 37.7 F 4.03 36.3 MF 3.93 37.1 Day 14 4 80 M 88.7 1390 F 410 6820 MF 249 4110 Day 90 3 40 M 8.68 132 F 35.0 526 MF 21.9 329 4 80 M 21.4 352 F 141 2310 MF 75.8 1240 Notes: Doses were administered twice daily approximately 8 hours apart. Due to limited concentration data above the lower limit of quantitation in males, only females are presented for Day 1 at 40 mg/kg/day.

TABLE 11-2 Summary of the Mean IPI-230 C_(max) and AUC₀₋₂₄ in Gottingen Minipig ® Plasma Patidegib Dose Level C_(max) AUC₀₋₂₄ Interval Dose Group (mg/kg/day) Sex (ng/mL) (ng · hr/mL) Day 14 4 80 M 1.56^(a) 27.2^(a) F 3.47 61.2 MF 3.15 55.5 Day 90 4 80 M 0.567^(a) 3.35* F 1.64 25.5 MF 1.28 18.1 Note: Doses were administered twice daily approximately 8 hours apart. *Value is not a mean (N = 1) and is presented for informational purposes only.

The mean concentration-time profiles of patidegib in plasma for the test groups (male and female results combined) are presented graphically in FIG. 6A and the mean concentration-time profiles of IPI-230 in plasma for the test groups (male and female results combined) are presented graphically in FIG. 6B. The dose normalized C_(max) and AUC₀₋₂₄ relationships of patidegib in Gottingen Minipig® plasma are presented graphically in for the combined sexes in FIGS. 7A-7B.

While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope. 

It is claimed:
 1. A composition for intradermal delivery, comprising: a hedgehog inhibitor compound and a solvent system comprising (i) a monohydric primary alcohol and a polyol in a w/w ratio of between about 0.9-1.8 and (ii) a buffer or a fatty acid comprising between 13-22 carbon atoms, wherein the hedgehog inhibitor compound is present in the solvent system between about 0.1-10 wt %, wherein the hedgehog inhibitor compound is patidegib or itraconazole.
 2. A composition for intradermal delivery, comprising: a hedgehog inhibitor compound and a solvent system, the hedgehog inhibitor having a saturation solubility in the solvent system of between about 2.5-8 wt % and the solvent system comprising between about 15-60 wt % of a monohydric primary alcohol and between about 10-50 wt % propylene glycol, wherein the hedgehog inhibitor compound is patidegib or itraconazole.
 3. A composition for intradermal delivery, comprising: a hedgehog inhibitor compound and a solvent system comprising (i) a monohydric alcohol comprised of at least one of ethanol and benzyl alcohol and propylene glycol, the monohydric alcohol and propylene glycol in a w/w ratio of between about 0.9-1.8 and (ii) a buffer or a fatty acid comprising between 13-22 carbon atoms, wherein a hedgehog inhibitor compound is present in the solvent system between about 0.1-10 wt %, wherein the hedgehog inhibitor compound is patidegib or itraconazole.
 4. The composition of any one of claims 1-3, wherein the monohydric alcohol is represented by the structure CnH2n-OH, where n is 1, 2, 3 or
 4. 5. The composition of claim 4, wherein the solvent system further comprises diethylene glycol monoethyl ether.
 6. A topical delivery system, comprising an intradermal composition according to claim
 1. 7. The topical delivery system of claim 6, further comprising a backing member and membrane joined to define a reservoir in which the composition is contained.
 8. The topical delivery system of claim 7, wherein the membrane is a non-rate controlling membrane.
 9. A composition for intradermal delivery, consisting essentially of: patidegib and a solvent system comprising ethanol and propylene glycol in a w/w ratio of between about 0.9-1.8, wherein the patidegib has a saturation solubility in the solvent system of between about 2.5-8 wt % and wherein formulation provides an in vitro concentration of patidegib in each of the dermis and epidermis of greater than about 250 μM 48 hours after topical application.
 10. The composition of claim 9, wherein the solvent system further comprises a fatty acid comprising between 13-22 carbon atoms. 